Mixed Prairie - I

The ultimate reference for mixed prairie (and shortgrass prairie) from standpoint of descriptions of range vegetation and response to disturbance is--and will likely always be--the classic Grasslands of the Great Plains by Weaver and Albertson (1956). Definitive source of knowledge regarding mixed paririe from an ecosystem perspective is that of Coupland (in Coupland, 1992, ps. 151-182). The comprehensive monograph on shortgrass plains (=prairie, steppe) edited by Lauenroth and Burke (2008) overlapped--by necessity--parts of the mixed prairie so as to be a valuable reference for western extremities of mixed prairie.

5BLotebush in bloom- Blooming shoot (upper photograph) and detail of inflorescences (lower photograph) of lotebush or gray-thorn. Lotebush has a wide species range that extends from the Rolling Red Plains of Texas westward to the Colorado Desert of southern California and south into Chihuhua and Sonora. This species has to have tremendous ecotypic variation.

Maricopa County, Arizona. June.

5C. Trunks of an oldster- Several woody shoots (trunks or boles) of an obviously old lotebush in the Rolling Red Plains of west Texas. Revealingly instructive views of the s;hoots of this shrub were possible at phenological stage of winter dormancy (leaves were shed).

Scurry County, Texas. Late February.

6. Mixed prairie-mesquite savanna- Mixed prairie of blue grama, sand dropseed, sideoats grama, galleta, buffalograss, curly mesquite, and little bluestem with a relative abundance of honey mesquite such as to form a grass-shrub savannah. The species composition and physiogonomy of this range plant community was interpreted by the author as representing an example of vegetation similar to the rangeland cover type described by the Society for Range Management (Shiflet, 1994) as Mesquite-Grama (SRM 718) and as a representation of the potential natural vegetation mapped by Kuchler (1966) as a gramagrass-buffalograss-mesquite community (one of the units designated as Grassland and Forest Combinations).

The relative density and cover of honey mesquite (Prosopis glandulosa) on the virgin grasslands prior to the heavy hand of the white man as a stock-raiser, teamster, farmer, oilman, road-builder, etc. will remain "known but to God". There will always be arguments as to the extent and ecological role of this native legume on the natural grasslands, shrublands, and savannas within the biological range of mesquite. Even use of terms like grasslands and savannas reflects biases (including those based on sound, well-conducted research) because such designations of vegetation indicate assumptions about relative absence of mesquite (on grasslands), limited presence of mesquite (savanna), or presence of mesquite as a dominant or at least influencial species (on shrublands or even forests).

Accounts by such diverse frontiersmen as buffalo runners, freighters, soldiers, and pioneer cattlemen made it quite clear that the Southern Great Plains had relatively little mesquite (at least that of such size, density, and cover as to be obvious) except in isolated groves, along watercourses, on breaks sites, etc. Buffalo chips not mesquite wood was the more usual fuel source on the vast southern grasslands of the interior of semiarid North America. However as soon as farmers began to break the virgin sod-- and break plow shares and tongues on big mesquite lignotubers beneath the soil surface-- it became apparent that there had been more mesquite than was realized. Fires set by lightening and Indians had kept mesquite shoots burnt back to inconspicuous size. Perhaps browsing by such native herbivores as buffalo, elk, or even rodents and lagomorphs had been a factor that maintained mesquite and other woody range plants at lower population levels and in subordinant (vs. dominant) ecological roles. The "pet" theory among the first cattle-raisers as to the most important animals feeding on mesquite (and thereby keeping mesquite in check) was the prairie dog. Old-time cowmen made the connection in their observations between prairie dog eradication programs ("poisoning champaigns") and mesquite invasion.

That there has been a great increase in density and cover of mesquite across rangelands of southwestern North America is beyond doubt or debate, but the degree and origin or cause of this increase is widely debated, discussed, cussed, and published. Nobody half-way knowledgable of the subject can argue against some role of overgrazing, cessation of fires (both atmospheric and anthropogenic in origin), farming, oil and gas development, commercial trade (as in trail- road-building), and even some climatic changes. Perhaps the history of mesquite invasion from perspective of causes is unimportant in a practical sense except to use such knowledge to try to "stem the tide". But knowledge as to the relative "amounts" of mesquite in the various plant communities (range types) in pre-Columbian vegetation would be invaluable in establishing "base lines" or "benchmarks" from which contemporary resource managers like rangemen could measure departure from the potential natural vegetation. (It should be borne in mind, always, that the current potential natural vegetation may differ drastically from pre-white man potential natural vegetation, or for that matter, pre-red man.)

The relative emphasis on mesquite (and mesquite reduction) as a major problem (and goal) in management of brush-infested ranges (including those where mesquite is only one of many brush species) has varied over time with changes in market value of commodities and the latest academic fad and barrage of "buzz words". Emphasis and perception of the mesquite problem has swung widely from the optimistic utopia of mesquite eradication (destroy every last smidgen of it) to the equally naive-- and idiotic-- misconception that because some mesquite is valuable for deer habitat it ought to be increased on ranches that sell hunting leases. In between these mesquite-mood swings even the realistic professional goal of some degree of control of this noxious range plant has varied with changes in control costs, cattle and real estate markets, oil royalties, and rainfall.

How much mesquite should there be? The answer to that question will always vary from one pasture, one operation, one public park, etc. to the next as well as in conjuction with the factors just noted. How much mesquite was there? The answer to that question, which contemporary rangemen will never really know, also varied from one range site, one precipitation zone, one fire regimen, etc. to the next. It also depended on what point in time and the time span that the question referred to. Undoubtedly, relative abundance of mesquite varied over time scales that ranged from a few growing seasons to the end of one drought to start of the next drought to the longest period of a major climatic shift.

The relative proportion of honey mesquite on this mixed prairie was viewed by this author as being roughly the maximum amount of mesquite that could occur on climax mixed prairie (within the grassland or grass-shrub savanna based on pre-Columbian potential natural vegetation). Vegetation of the High Plains and Rolling Red Plains having mesquite populations greater than the general approximation represented by the plant community in this photograph would be in a state of retrogression according to the judgment of this author. Others might opt for substantially more mesquite and relatively less grass. They can place their photographs and state their conclusions on their web sites. This author stands by the traditional conclusion that honey mesquite is, though a native species, an ecological invader on many (in Texas, most) grasslands and savannas and that control of this noxious species is one of the major challenges to sound range management.

Honey mesquite is one of the most important range brush species in North America (the most important statewide in Texas and parts of adjoining states). Stewardship of range resources demands that mesquite be attacked with the full arsenal of current science and technology consistent with economic feasibility. And go at it "with a vegeance"!

In the context of range cover types and use of climax vegetation as a benchmark with which to measure management it will be recalled here that departure from climax is neither proper nor improper management until specific objectives-- based on ecological as well as economic principles-- are established.

Chaves County, New Mexico. June (and a dry one). FRES No.38 (Plains Grasslands Ecosystem). K-76 (Mesquite-Buffalograss; Bouteloua, Buchloe, Prosopis). SRM 718 (Mesquite-Grama). (The example of vegetation in this photograph grew west of where K-76 was mapped. It was interpreted as an "island" of the larger mapping unit, such smaller outliers of the larger mapping scale not having been delineated by Kuchler.) Mixed "Short-Grass" Series of Brown et al. (1998). Southwestern Tablelands- Conchas/Pecos Plains Ecoregion, 26n (Omernik and Griffith, 2006).

7. Mixed prairie-mesquite savanna in Texas Rolling Red Plains- This was a good example of the now nearly ubiquitous mesquite mid-grass range of the south-eastern portion of the Great Plains region. The original mixed prairie, a climax grassland type of tallgrass, mid-grass, and short grass layers, has become degraded (for whatever combination of reasons and factors) by woody plant invasions accompanied by nearly complete loss of the tallgrass element and a mid-grass layer comprised mostly of increasers and invaders. In this example sideoats grama, the climax dominant for this cover type, was reduced and largely replaced by threeawns, most notably Wright's threeawn (Aristida wrightii= A. purpurea var. wrightii). Other major mid-grasses included silver bluestem and sand dropseed. Hairy grama was locally dominant growing to dimensions and densities more typical of a mid-grass such as sideoats grama. There were distinct "patches" (microsites) of shortgrasses of buffalograss and blue grama (in that order). One such "patch" was visible in front and to left of the honey mesquite.

Rolling Red Plains of the Great Plains physiographic province.

Pitchfork Ranch, Dickens County, Texas. Estival aspect. August. FRES No. 38 (Plains Grasslands Ecosystem). K-76 (Mesquite-Buffalograss; Bouteloua, Buchloe, Prosopis). SRM 718 (mesquite-grama cover type). Mixed "Short-Grass" Series of Brown et al. (1998). Mixedland range site. Southwestern Tablelands- Flat Tablelands and Valleys Ecoregion, 26b (Griffith et al., 2004).

8. Rough land mixed prairie-redberry juniper (Juniperus pinchotii) savanna- Across many acres of mixed prairie range redberry juniper takes the place of honey mesquite as the dominant woody invader. Occurrence of redberry juniper as the dominant invader tends to be on rangeland with more prominent dendritic drainage patterns (ie. "rough land") especially near breaks sites that, being less prone to fire, serve as reserviors for seed-producing woody plants. Redberry juniper is fire-adapted being one of the rare sprouting conifers.In this example, a range infested with redberry juniper had been treated by prescription burning seven growing seasons previously. Redberry juniper had resprouted plus some of the original junipers had been "passed over" by the prescribed fire.

Herbaceous vegetation consisted of both mid-grass and shortgrass layers. The major mid-grass species was sideoats grama. In places sideoats was dominant. Other mid-grasses included silver bluestem and sand dropseed. Hairy grama was often the local dominant and it appeared to have a role more like that of a mid-grass, especially sideoats grama. Buffalograss was the major short grass species. It was associated with blue grama that grew to size more that of a short grass. Soapweed (Yucca glauca) was an associate shrub species.

Great Plains phyiographic province; Rolling Red Plains component (east of Caprock escarpment).

Pitchfork Ranch, Dickens County, Texas. Estival aspect. August. FRES No. 38 (Plains Grasslands Ecosystem). K-76 (Mesquite-Buffalograss; Bouteloua, Buchloe, Prosopis). SRM 718 (mesquite-grama) or SRM 727 (mesquite-buffalograss). SRM designation was confusing. In protected areas sideoats grama was dominant which fit descriptions of both 718 and 727. This in conjuction with local dominance of hairy grama plus prescence of blue grama in shortgrass "patches" qualified this vegetation as SRM 718 (mesquite-grama). Conversely, presence of redberry juniper as the dominant woody plant fit the variant description of SRM 727 (mesquite-buffalograss) except that buffalograss was far from dominant. The reader can reach his own conclusion. Mixed "Short-Grass" Series of Brown et al. (1998). Mixedland range site. Southewestern Tablelands- Flat Tablelands and Valleys Ecoregion, 26b (Griffith et al., 2004).

9. Advance of the enemy- Mixed prairie with onset of redberry juniper invasion. This was part of the same pasture presented in the two immediately preceding photographs except that here brush was sparse. Woody invasion was underway nonetheless. Recurrent fire-- natural or prescribed-- would prevent or reduce onset on a further brush problem.

This vegetation consisted of two herbaceous layers: 1) mid-grass dominated by Wright's threeawn with sideoats grama the associate and silver bluestem and sand dropseed locally common and 2) short grass consisting of buffalograss and blue grama.

Pitchfork Ranch, Dickens County, Texas. Estival aspect. August. FRES No.31 (Plains Grassland Ecosystem). K-76 (Mesquite-Buffalograss; Bouteloua, Buchloe, Prosopis). SRM 718 or 727 (see explanation in preceding caption). Mixed "Short-Grass" Series of Brown et al. (1998). Mixedland range site. Southwestern Tablelands- Flat Tablelands and Valleys Ecoregion, 26b (Griffith et al., 2004).

10. Sward of mixed prairie with two herbaceous layers- The distinct mid-grass and short grass strata of a mixed prairie were shown in these two slide. No, this was not spot grazing (at least not in the current growing season). The "spot" with grass of lower height was comprised of buffalograss and blue grama whereas the larger "spot" consisted of Wright's threeawn, sideoats grama, silver bluestem, and sand dropseed. Presence of smaller, "stunted"-appearing individuals of threeawn in the "low plant spots" and presence of some-- though restricted in cover and density-- buffalograss and blue grama among the cespitose mid-grasses suggested that past (previous seasons) spot grazing may have contributed to occurrence of the "patches" dominated by short grass species. Localized heavier utilization was clearly not the only factor, however, as this plant community pattern has been seen frequently on areas protected from grazing (eg. on steep slopes and larger canyon faces of breaks sites). Besides, on this site blue grama is generally interpreted as a decreaser while buffalograss is classified as an increaser. Yet these two species grew side-by-side in this vegetation. It was likely that soil differences at microsite scale were also factors in this mosaic of short grass and mid-grass.

Pitchfork Ranch, Dickens County, Texas. Estival aspect. August. FRES No. 31 (Plains Grassland Ecosystem). K-76 (Mesquite-Buffalograss; Bouteloua, Buchloe, Prosopis). SRM 718 or 727 (see explanation two captions above). Mixed "Short-Grass" Series of Brown et al. (1998). Mixedland range site. Southwestern Tablelands- Flat Tablelands and Valleys Ecoregion, 26b (Griffith et al., 2004).

11. Honey mesquite as a nurse plant- The nurse plant phenomenon has been described in the literature and is textbook knowledge (eg. Barbour et al., 1999, ps.153-156). Nurse plant relationships have been interpreted as a form of commensalism, those interactions which are positive or beneficial for one species (the "nursee") and neutral (having no meaningful impact) on the other species (the "nurser", which is mesquite in this instance). Honey mesquite functions as a nurse plant to many plant species, likely to as many or more than any other plant on the ranges of North America. This is more so in the Rio Grande Plains grass-shrub savanna than on the mixed prairie grasslands like those of the Rolling Red Plains. Even on the latter, as shown here, mesquite "plays host" to several other shrub and tree species. In this Red Plains case sugar hackberry (Celtis laevigata), lotebush, and brownspine prickleypear (Opuntia phaeacantha) have come in under the shade and moderated microenvironment afforded by honey mesquite. The most important outcome of the mesquite nurse plant drama is that mesquite-infested ranges become multi-storied, mixed-species brush thickets with noxious plant control much more complicated thereby requiring more elaborate and expensive control methods and greatly decreasing the likelihood of grassland restoration.

Taylor County, Texas. October. FRES No. 38 (Plains Grassland Ecosystem). K-76 (Mesquite-Buffalograss; Bouteloua, Buchloe, Prosopis). SRM 718 (Mesquite-Grama) in advanced retrogression.

12. Mixed species brush invasion on Rolling Red Plains mixed prairie- This is an example of the nurse plant relationship carried to it's ultimate development: mature and reproducing honey mesquite forming both canopy and part of a middle woody understorey layer with young sugar hackberry and large lotebush comprising a second brush layer and brownspine prickleypear as the latest and lowest growing shrub starting to development into a third woody plant layer. All three (or more) brush layers are more dense and taller than (and taking light and water from) what is left of the mid- and shortgrass species.

It is difficult to find "middle ground" with mesquite on grassland or savanna. Honey mesquite is a natural "monopolist". It will gain effective total control over resources required for plant growth, and bring it's co-conspiring, resource-dominating, robber baron buddies right behind it. FRES No. 38 (Plains Grassland Ecosystem). K-76 (Mesqujite-Buffalogreass, Bouteloua, Buchloe, Prosopis). SRM 718 (Mesquite-Grama) in ultimate state of ecological deterioration.

13. Mixed prairie in the Kansas Red Hills- Physiography of the northern limit of the Rolling Redlands or Rolling Red Plains and the physiogonomy of mixed prairie. Mixed prairie is the climax vegetation of this physiographic unit of the Great Plains or, according to some, the Plains Border. Presented here is the north end of a physiographic sub-province that begins in Texas and extends northward through Oklahoma following what was termed the Break of the Plains. In the Texas and Oklahoma Panhandles this break is very prominent where the western edge of the Rolling Red Plains meets the Southern High Plains. The persistent mantle of the High Plains or Llano Estacado (Staked Plains) is known as the Caprock Escarpment. Immediately east of the Staked Plains, then, is a geologic/edaphic region known, again, as the Rolling Red Plains or, still yet another synonym, Redbeds Plains. In Kansas this has traditionally been called the Red Hills. The definitive physiographic reference remains Fenneman (1931, ps. 25-30; 1938, ps. 606, 617-620).

The Redbeds Plains region had (has) some of the best developed mixed prairie vegetation. Much-- probably most-- of this general range type was either destroyed by the plow or, in Texas and southern Oklahoma, converted to a mesquite (Prosopis glandulosa) shrubland disclimax by a combination of overgrazing, underburning, oil and gas development, perhaps even by faunal changes and climatic shifts, and God alone knows what else. As if that was not enough, most of the mixed prairie that escaped the plow and the brush is in some state of vegetational retrogression (ie. range deterioration), some more so than others.

The mixed prairie vegetation shown in this and the next two slides was in the Kansas Red Hills and was in high Fair to low Good range condition class. These three photographs were followed by four photographs of mixed prairie sward in Excellent range condition class, but this latter vegetation was in the Southern High Plains province immediately north of the Red Hills.

In the present slide vegetation in the foreground is outside a pasture fence of a large ranch. This relict vegetation served as a reference which was compared to the climax or potential natural vegetation described in Soil Sruveys. The range plant community in this "control plot" was dominated by the Four Horsemen of the Prairies tallgrass species. Both big bluestem and sand bluestem were the most common, but Indiangrass and switchgrass were also locally abundant. In this authors experience this was tallgrass prairie vegetation in having big and sand bluestem in the same general range plant community. Big bluestem grew on bottomland land and up through midslope while sand bluestem grew on top of ridges and, as would be expected, in microhabitats of deeper sand. Little bluestem was locally abundant. Canada wildrye, prairie dropseed, and tall dropseed were also abundant as was sideoats grama and buffalograss to add a definite and distinctive mid-grass and shortgrass layer to the vegetation and it's physiogonomy. Leadplant was the most common legume, but the dominant forb (and locally dominant plant) was Louisiana mugwort or Louisiana sage or white sage (Artemisia ludoviciana). There were large but local colonies of goat's rue (Tephrosia virginiana).

Vegetation in the background of this slide was presented in the next two slides. This photograph gave a representative landscape-scale view of Red Hills mixed prairie.

Barber County, Kansas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Predominant range site was Loamy Upland with smaller areas of Shallow Prairie. Southwestern Tablelands- Cimarron Breaks Ecoregion, 26a (Chapman et al., 2001).

14. Mixed prairie in Kansas Red Hills- Landscape view that encapsulates the "lay of the land" and the diverse grassland vegetation of mixed prairie in the rolling plains landform of the Plains Border. This land and, some to some extent, its vegetation is a transition between that of the Central Lowlands with it's tallgrass and true prairies and the Great Plains with it's mixed prairie and shortgrass plains. This ecosystem (perhaps the ecological unit of landscape is more appropriate) can be visualized as "ecotonal" between the High Plains portion of the Great Plains and the Prairie Plains of the Central Lowland physiographic provinces.

The vegetation presented here was an accurate composite of that of the Red Hills in Fair to Good ecological (range) condition class. The aspect dominant at this point in progression of the growing season was silver bluestem. It was likely that little bluestem was the overall dominant, but it was much less conspicuous than silver bluestem at phenology of full bloom and peak standing crop. (The largest-- but scattered-- grass clumps are little bluestem). Prairie dropseed was common, but the more mesic and productive species of big bluestem and/or sand bluestem (dominant in protected areas), Indiangrass, and switchgrass were relatively scarce in the range vegetation displayed here. The increaser to invader (site-dependent) tumble windmillgrass (Chloris verticillata) was locally abundant. Western wheatgrass, sand dropseed (Sporobolus cryptandrus), and tall dropseed (S. asper) were present in small amounts. Sand sagebrush (Artemisia filifolia) was the major shrub with common soapweed or yucca (Yucca glauca) present but far from common. Louisiana mugwort was locally abundant (note small, short forb in immediate lower left foreground). Buffalograss was dominant (as the sole species) across wider microsites (the tan-colored spaces on the diagonal ridge tops).

Barber County, Kansas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosytem). K-62 (Bluestem-Grama Prairie). SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Primarily Loamy Upland range site with smaller areas of Shallow Prairie range site. Southwestern Tablelands- Cimarron Breaks Ecoregion, 26a (Chapman et al., 2001).

15. Red Hills mixed prairie (bluestem-grama grassland) community- Detail view of vegetation shown in the two preceding photographs. The larger tufts were little bluestem and silver bluestem which comprised more of the interspace than any other species with sand dropseed second. Sideoats grama, hairy grama, and buffalograss were also common with buffalograss often forming exclusive colonies or stands. The prominent forb in the immediate foreground was Louisiana sage or Louisiana mugwort. Sand sagebrush was the only shrub and it was quite rare (none of it was visible from this vantage point).

Range condition class was high Fair there being almost no big bluestem (the potential dominant), Indiangrass, or switchgrass. On the other hand, invaders like red threeawn (Aristida longiseta), alien annual annual bromes (eg. Bromus japonicus), and weedy Eurasian forbs such as Kochia scoparia were absent indicating that this range was also a "fur piece" from Poor or even low Fair condition class. No accelerated soil erosion was occurring.

Barber County, Kansas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Loamy Upland range site. Southwestern Tablelands- Cimarron Breaks Ecoregion, 26a (Chapman et al., 2001).

16. Louisiana mugwort, western mugwort, white sage, western wormwood (Artemisia ludoviciana)- This forb (primarily an herbaceous plant) is typical of the Artemisia species in being widely distributed (ie. having a large species range). This phenomenon is characterized by having several subspecies or varieties (often depending on which taxonomist's treatment is consulted). The colony of A. ludoviciana shown here was in the Rolling Red Plains of northcentral Texas in mid-spring. The official flora and manual of Texas did not follow the convention of subdividing this species because it was stated that there was little correlation between such taxa and geographic distribution of these subdivisions. Most other taxonomic workers in this geographic region disagreed.

Western mugwort is-- as obvious from this photograph-- a rhizomatous species having numerous daughter plants arising from older shoots which function as a parent plant (ie. another example of a clonal organism).

SMS Ranch, Throckmorton County, Texas. May.

17. Short and white- Local dense stand of white sage (Artemisia ludoviciana var. ludoviciana) in Central High Plains. This form of A. ludoviciana differs considerably from the much larger and heavily branched ecotypes found frther south (see below). This variation in morphology is consistent with the large biological range of this widespread species.

Washington County, Colorado. Mid June, pre-bloom stage.

18. A Great Plains form- Details of shoots (first slide) and leaves along with shoot apices (second slide) of (Artemisia ludoviciana var. ludoviciana). About everything from size to coloration is different in this smaller, paler variety of white sage as to compared to southern forms of Artemisia ludoviciana var. mexicana found farther east and south (see immediately succeeding slide from northeast Oklahoma).

Washington County, Colorado. Mid June, pre-bloom stage.

19. Adult plant of western or Louisiana mugwort at post-bloom stage- An extremely hearty individual of A. ludoviciana at the early to mid-fruit ripe stage growing on a oak-hickory- tallgrass savanna in the Ozark Plateau in eastern Oklahoma. Taxonomic treatments by authors in the florae of Missouri and the Great Plains keyed this specimen to A. ludoviciana var. mexicana in contrast to A. ludoviciana var. ludoviciana of the Great Plains physiographic province that was presented immediately above. Some authors treated these subdivisions as subspecies while others interpreted them as varieties. Does any of this matter?

Stoney Point Savanna, Ottawa County, Oklahoma. September.

20. Ruefully on mixed prairie range- Goat's rue (Tephrosia virginiana) growing on Kansas Redlands range. This dense local colony was growing just outside (protected side of the fence) of the Excellent condition range featured above. This highly palatable and nutritious papilionaceous legume is a decreaser and, like so many native legumes, is extremely difficult to maintain under realistic management of ranges (eg. the superbly managed mixed prairie grassland featured here). This species is also a favorite of native plant fanciers, but it is often difficult to get satisfactory results from seeding.

Burrows and Tyrl (2003, p. 636) reported that goat's rue roots contain rotenone and were used by American Indians to harvest fish. Goat's rue, however, is regared as nontoxic to birds and mammals given low toxicity of rotenone to warm-blooded species and the relatively low levels of this toxin in T. virginiana.

The one-page treatment of this species in the Phillips 66 Pasture and Range Plants (Phillips Petroleum Company, 1963, 2006) was recommended as an introduction to this colorful, native legume.

Barber County, Kansas.Late June (early summer), full-bloom phenology.

21. Colorful legume on Kansas Redlands range- Characteristic shape and color of goat's rue inflorescence.Plant taxonomists apparently cannot agree on which tribe to assign Tephrosia to. Some authorities interpreted the appropriate tribe to be Millettieae. Others still hold with the Tephrosieae (ie in its own tribe, basically). It seemed to this nontaxonomic author that most authorities regarded Tephrosia species as being in the Galegeae tribe which includes such important--and highly colorful--range legumes as the locoweeds or crazyweeds (Astragalus and Oxytropis spp.), lead plant (Amorpha spp.), and prairie clover (Petalostemon spp.).

Barber County, Kansas. Late June (early summer), full-bloom phenology.

22. Another gift from storms- Lightening was apparently the source of ignition for a fire that burnt off this Kansas Red Hills range just a few months before time of these photographs. The lightening and resultant range fire was a Godsend, a gift from above. Details of the wild fire--a natural fire (in this instance) but one that burned out of control over the range--were unknown to this reporter. Results of the lightening-set fire were obvious and presented here.

The most conspicuous impact (and certainly a benefical one) was total topkill of sand sagebrush (Artemisia filifolia) and large patches of Chickasaw plum (Prunus angustifolia). All these shrubs had promptly resprouted, but the big bluestem, sand bluestem, and Indiangrass had benefitted greatly from the fire that appeared to have encouraged greater tiller production and more shifted the competitive advantage from shrubs toward the prairie grasses, especially the tallgrasses. Almost all of the shrubs were several years old and the fire killed almost all of the aboveground portions of these woody species.

A followup fire probably would have had an even greater detrimental impact on shoots (and perhaps roots) of shrubs.

This was the same Red Hills mixed prairie (bluestem-grama grassland) range introduced above that was in Excellent range condition class. In fact, over course of the seven years/gorwing seasons that had passed between the above photographs and the two described here this cattle range had improved. This improvement was primarily from the criterion of greater absolute and relative propotions of tallgrass species in the plant community. Apparent cover of tallgrass species, especially sand bluestem, had increased noticably over the seven-year span. Except for the brush (ie. woody cover in excess of man's best judgment of woody cover in relict vegetation), which had also increased over this time frame, this was pristine mixed prairie grassland. It was a classic textbook example. Increased woody cover was greatest for Chickasaw plum which was nearly absent from this range seven years earlier.

With drastic reduction of excessive shrub cover, density, etc. stemming from God's own prescribed burn this range plant community was an even closer approximation of the virgin vegetation of mixed prairie in the Kansas Red Hills.

In addition to tallgrass species (big bluestem, sand bluestem, little bluestem, Indiangrass, upland ecotypes of switchgrass, tall dropseed, Canada wildrye) there was sand dropseed, silver bluestem, western wheatgrass, Scribner's rosette panicgrass (Panicum oligosanthes var. scribnerianum= P. scribnerianum) and sideoats grama as midgrasses as well as blue grama, hairy grama, and buffalograss for the major shortgrasses. Tumble windmillgrass, cheatgrass or downy brome, Japanese chess or Japanese brome were other grass species, but (as typical of climax mixed prairie) these were limited.

Major forbs at this society (in this plant society) included wild alfalfa or slimflower scurfpea, western ragweed (Ambrosia psilostachya), goat's rue, white sage or white mugwort, silverleaf nightshade (Solanum elaeagnifolium), and buffalobur (S. rostratum) with dominance and relative proportions varing tremendously at local scale.

Soapweed yucca was also present. (The author left it up to readers to call Yucca glauca a shrub or forb; it can qualify as either or both.)

The first of these two photographs presented the general landscape of this burnt mixed prairie with a larger sand sagebrush that had been completely topkilled by the range fire, but which had quickly and vigerously resprouted soon thereafter. In the background were several large colonies of Chickasaw plum that were topkilled. Most of the grass in the foreground of this first slide was sand bluestem. Other identified grasses included silver bluestem, sideoats grama, and hairy grama.

The second photograph was the interior of a thicket of Chickasaw plum that had complete topkill resulting from the wild fire. There were a few plants of sand sagebrush in this thicket. Both plum and sagebrush had resprouted, the sand sagebrush much more aggressively. Most of the new vegetative growth, however, was sand bluestem and Indiangrass with quite a few plants of Scribner's rosette panicgrass. There was also a lot of silverleaf nightshade coming up after this fire as well as quite a bit of cover of western ragweed. Fire on mixed prairie kills several year's growth of aboveground perennating parts of woody plants, but if the fire takes place in the dormant season it removes nothing but dead shoots of herbaceous plants. (Even if fire burns grass during growth it removes only one year's grwoth at most, although grass may be harmed beyond one year's growth.) This is the selective defoliation by fire. The competitive advantage immediately shifts in favor of herbaceous species, the dominants of which on this Excellent condition class range were tallgrass species like big and sand bluestem and Indiangrass.

Note on brush: Eastern red cedar (Juniperus virginiana) has become a major invader of rangelands in the Kansas Red Hills. Eastern red cedar is a native conifer, but one under natural conditions that was confined to rough breaks and related range sites too xeric or otherwise too harsh to grow herbaceous fuel adequate to a carry cedar-killing fire. Eastern red cedar is a non-sprouting species so frequent fire eliminates this species from mixed prairie ranges. In absence of range burning in recent decades eastern red cedar developed into a major threat to structure, function, and overall integrity of mixed prairie ecosytems in this region the same as over much of the tallgrass prairie. The Excellent condition class mixed prairie range described here was not infested with eastern red cedar, but this coniferous invader was in mixed prairie range just across the highway from this mixed prairie vegetation. Obviously, past range fires had blessed the range featured here. A less fortunate, cedar-infested mixed prairie on the other side of the road was presented below.

Barber County, Kansas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Loamy Upland range site. Southwestern Tablelands- Cimarron Breaks Ecoregion, 26a (Chapman et al., 2001).

23. It all sprouts back- Vegetation of a mixed prairie range in the Kansas Red Hills about two months into the warm-growing season following a fire that topkilled sand sagebrush and Chickasaw plum and released numerous herbaceous species. The major of these herbaceous plants in the seen in thsi photograph was sand bluestem, one of the dominant species of this climax plant community. Other herbaceous species that promptly grew after the wild fire and were visible in this "photoquadrant" included Scribner's rosette panicgrass, big bluestem, sideoats grama, silverleaf nightshade, buffalobur, and western ragweed.

Sand sagebrush also promptly resprouted following the fire. The heat-blanched linear leaves at upper right were those of a topkilled Yucca glauca which had not resprouted, but which probably would as this is a sprouting species.

Barber County, Kansas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Loamy Upland range site. Southwestern Tablelands- Cimarron Breaks Ecoregion, 26a (Chapman et al., 2001).

24. Resprouting shrub and resprouting grass- Shoots of sand sagebrush and sand bluestem in teh Kansas Red Hills following a wild fire earlier in the year. The first of these two photographs was of rapid shoot growth by sand sagebrush following the fire.Not all Artemisia species resprout following firekill of the existing shoot, but A. filifolia is a vigerous sprouter. This species is obviously adapted to fire, but recurrent fire (as in repeated prescribed burning) will limit sand sagebrush to minimal cover because native tallgrasses like sand bluestem are even better adapted to recurrent fire. Numerous shoots of silverleaf nightshade were also present (and released) beneath the former crown canopy of sand sagebrush.

The second photograph presented vigerous tiller release of sand bluestem following the burn. There were also numerous shoots of silverleaf nightshade, buffalobur, and western ragweed, but these would be over-towered and over-shadowed (probably overwhelmed in general) by sand bluestem. Just hide and watch.

Barber County, Kansas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Loamy Upland range site. Southwestern Tablelands- Cimarron Breaks Ecoregion, 26a (Chapman et al., 2001).

25. Comparison: the result of fire exclusion- Directly across a two-lane highway from the Excellent condition mixed prairie range just described there was another mixed prairie here in the Kansas Red Hills. This overgrazed range had become badly infested with sand sagebrush, Chickasaw plum, and eastern red cedar. These woody scurges were the uncontrovertable outcome of the dual sins of 1) overgrazing and 2) underburning. The conspicuous white composites were daisy or prairie fleabane (Erigeron strigosus). The dead grass was both species of annual brome: Japanese chess and cheatgrass or downy brome. But look at the green grass (and read below...).

What else can be said? A lot actually. This range was in high Poor to low Fair condition class with this low successional status due primarily to the relatively high percentage of woody invaders. The vegetation of this range stood in stark contrast to that of its neighbor. Sound range management made the difference. The good steward and the poor steward: the proper choice was clear, and the rangeman has the freedom of choice.

The real lesson to be learned from this example is in the herbaceous species. The large green leaves were those of sand bluestem and big bluestem. Indiangrass was also present as were most of the same grasses in the Excellent range across the road. The major grasses were tallgrass species. They were relatively obscure-- compared to prominence of bigger (and getting bigger all the time) cedars, plum thickets, and sagebrush, but the tall-growing, potentially dominant decreaser grasses s .were there just waiting to be released from suppression by the brush.

Furthermore, eastern red cedar is a nonsprouting species. A topkilled Juniperus virginiana is a dead cedar, end of story for that plant. Yes, the plums and sagebrush will resprout. To a point that is also good because some cover of these native shrubs is desirable as cover for wildlife as well as being component species of the mixed prairie plant community. To a point. Cover of these two species (eastern red cedar is probably not native to this range site under natural fire regimes) was far in excess of natural proportions. Proper grazing and wise use of fire can keep them "in their place" and not as brush.

This was not a tale of "gloom and doom". All was not lost. This range still had the potential to recover to Excellent condition, to once again be pristine mixed prairie. That was the promise of faithful stewardship.

Barber County, Kansas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Loamy Upland range site. Southwestern Tablelands- Cimarron Breaks Ecoregion, 26a (Chapman et al., 2001).

26. Is this an alternative to fire?- A cattle range of mixed prairie (bluestem-grama grassland) in the Red Hills of Kansas that had serious invasion of various species of brush, primarily eastern red cedar (Juniperus virginiana) and and sand sagebrush (Artemisia filifolia). This range was in in Fair to low Good range condition class that could be quickly improved first and most importantly by brush control and secondly by better grass management, including use of prescribed burning. Actually prescribed fire would be the tool of choice for both of these range improvement practices.

This specific pasture was on the opposite side of a state highway (Kansas ) from the pasture burnt by wild fire that was discussed immediately above. On this side of the road ranchmen had used a chainsaw to fell most of the larger eastern red cedar, but leaving smaller seedlings and saplings of this conifer as well as all of the sand sagebrush. Is this treatment a substitute for a properly conducted prescribed burn? It appeared to this observer that for purposes of brush reduction burning fuel on the range was more effective than burning it in the chamber of a chainsaw. Viewers will decide for themselves.

Berber County, Kansas.

27A. This is a textbook example of the species composition, physiogonomy, and community structure of mixed prairie on the Southern High Plains. In this one photograph can be seen the tallgrass species of big bluestem, Indiangrass, and upland switchgrass; mid-grasses like sideoats grama and silver bluestem; and the shortgrass species of hairy grama, buffalograss, and a "smigen" of blue grama. Western wheatgrass was absent. The dominant forb was wild alfalfa (Psoralea tenuifolia).

Invaders like red threeawn, annual Bromus species, broom snakeweed, and sand sagebrush "were conspicuous by their absence".

27B. Characteristic sward of mixed prairie in the Southern High Plains- The combination of bunchgrass and bare soil with the dense turf formed by sod-forming grass is one of the most obvious physiogonomic features of this multi-storied grassland.There were the three layers formed by the tall-, mid- and shortgrass species with scattered individual plants of the leguminous forb, wild alfalfa. A shrub layer and soil surface layer (eg. of mosses, lichens, fungi) were both absent.

28. Along the old Santa Fe Trail- The mixed prairie range shown here was not in as high a successional state as the Excellent condition class just presented, but it was more typical (plus it afforded a history lesson)- Example of degraded--though recovering nicely--mixed prairie vegetation with a real diversity of plant species. Rangeland seen here was upland mixed prairie redeveloping back to climax vegetation on the Santa Fe Trail. Secondary succession was revegetatiing the ruts of one of the most famous and important routes of commerce in the history of the United States of America.

This deeply rutted, eroded land was one of the original "interstate" (interterritorial to be more accurate) Anglo-American highways west of the Missouri River. The Santa Fe route of commerce was the connection of the Anglo-American Midwest to the Spanish-Mexican Southwest that was headquarted out of Santa Fe. This trading hub was the northern terminus of the Camino Real or King's Highway (the full name was El Camino Real de Tierra Adentro, meaning in English, Royal Road to the Interior) while the southern terminal was Mexico City. (Santa Fe later become the capital of New Mexico with final triumph of the United States over Mexico). Incidentially, range vegetation along the Camino Real was described in the Shrublands chapter, Chihuhuan Desert.

The mule skinners and bull whackers were the Nineteenth Century equivalent of truck drivers. One of their more powerful unions still bears the name of these forebears, Teamsters, and the energy delivered by their diesel engines is still measured as horse power.

The natural vegetation along the now-abandoned trade route is still the same except for successional changes wrought by heavy traffic. Now even the grassland vegetation of disturbance is, through plant succession, slowly though inexorably returning to the mixed prairie community that was present long before the crack of bull whip and the cussing-accompanied ox goad wrote an exciting chapter in frontier history.

This range vegetation was tremendously rich in species of grasses and forbs. Grasses included big bluestem, little bluestem, silver bluestem, western wheatgrass, sideoats grama, blue grama, hairy grama, common of tumble windmillgrass (Chloris verticillata), buffalograss, and red threeawn (Aristida longiseta), bottlebrush squirreltail (Sitanion hystrix), cheatgrass of downy brome, Japanese brome or Japanese chess. Forb included wild alfalfa or slimflower scurfpea, common or white milkwort (Polygala alba), citron (Indian) paintbrush (Castilleja purpurea var. citrina), Carruth's sagewort or sage (Artemisia carruthii), and showy milkweed (Asclepias speciosa).

Gray County, Kansas. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). Northern variant of SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Western High Plains- Flat to Rolling Cropland Ecoregion, 25d (Chapman et al., 2001).

29. Recovery on the ruts- Two "photoplots" of recovering mixed prairie range on the famed Santa Fe Trail. Most of the range plants at this phase of the annual growth cycle were forbs. Silver bluestem, blue grama, sideoats grama, and common or tumble windmillgrass were common in the first "plot", but even at that the more common--and certainly more conspicuous--species were wild alfalfa or slimflower scurfpea, Carruth's sagewort or sage, citron paintbrush, and showy milkweed. The seocnd "photoquadrant" featured wild alfalfa or slender scurfpea, Carruth's sagewort or sage, and citron paintbrush growing with blue and sideoats grramas.

Gray County, Kansas. Late June (early estival aspect; peak bloom and standing crop of several forb species). FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). Northern variant of SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Western High Plains- Flat to Rolling Cropland Ecoregion, 25d (Chapman et al., 2001).

30. Yellow markers along the Santa Fe Trail- Citron paintbrush (Castilleja purpurea var. citrina) growing on the rutted rangeland of the former Santa Fe Trail, one of the most colorful and critical trade routes in the history of the Trans Mississippi West. Nature was healing her own in her own way. Secondary plant succession was revegetating mixed prairie grassland that had been drastically altered by the frontier equivalent of an interstate highway for mule trains and oxen-powered freight wagons. If one listens carefully he can hear the cussing of the bull whackers while enjoying the unusual color of the citron paintbrush. Well, at least hear the wind rustle through the paintbrush as it sweeps ceaselessly across the recovering Great Plains grassland.

Citron refers to yellow color (as in citrus frruits). MdGregor et al. (1986, ps. 761-762) described this species as having a woody crown (so do most other Castilleja species of the Great Plains) and with a corolla forming a "widely flaring lower lip". Most Castilleja species are root parasitic on composites.

Gray County, Kansas. Late June (early summer), peak-bloom stage of phenology.

31. A diverse herd of heavy steers (plus a buffalo for good measure)- Heavy grazing (apparently a modified form of intensive early stocking) of mixed prairie range. Grasses on this range included silver bluestem, big bluestem, whestern wheatgrass, sideoats grama, blue grama, and buffalograss plus some annual brome (more Japanese brome than cheatgrass or downy brome). The conspicuous species was wild alfalfa or slender scurfpea which produced a "bang-up" crop throughout much of the Southern High Plains in this growing season (rains must have come "just right" for this species). Cattle are not particularily fond of wild alfalfa (in spite of the name) and heavy stocking also might have favored growth of this legume. The othr major forb was Baldwin ironweed (Vernonia baldwinii).

Almost all of these steers--they were a motley herd if there ever was one--weighed in excess of 700 pounds and some were pushing 800. When the pork barrel, buy-corngrowers-votes subsidy for ethanol drove the price of the Midwest's number one fattening grain skyhigh steers were held longer as stockers to be sent into the feedyards at higher weights in order to reduce days on full-feed grain to a bare minimum. Steers were easily 200 pounds (sometimes considerably more) heavier when they went on and came off grass under such economic situations. That explained the large size of these cattle in early summer on the Southern High Plains.

The range manager must certainly take into consideration and factor in the greater size and forage intake when setting stocking rates which must be adjusted to run fewer head of heavier cattle. Otherwise stocking rates will be greater than usual and overuse of the range could occur only all too easily.

The author would have enjoyed a re-visit to this range in late August or early September just to see what the grass crop looked like after steers had been shipped and grass had a chance to recover (hopefully that is). Unfortunately, there was not a second visit and follow-up photographs. But there'll be another year ...

Kiowa County, Kansas. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). Northern variant of SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Central Great Plains- Rolling Plains and Breaks Ecoregion, 27b (Chapman et al., 2001).

Developing "smack-dab" in the heart of mixed prairie there was, in Clementsian monoclimax thoery, a postclimax tallgrass prairie. In polyclimax theory of Tansley and climax pattern theory of Whittaker, this range vegetation would be interperted as an edaphic climax. This grassland that was more mesic than that of surrounding mixed prairie had developed on deep, sandy soil in what is known as the Great Bend Sand Prairie. Regardless of theoretical perspective, this tallgrass sand prairie was dominated by sand bluestem (Andropogon hallii) and with Indiangrass and switchgrass as associates. An example of this sand bluestem-Indiangrass-switchgrass prairie that was Excellent condition class was growing "just down the road" from the mixed prairie range stocked with heavy steers presented immediately above.

This postclimax, edaphic tallgrass prairie was included at this juncture to illustrate to students how vastly different range sites can be over remarkablly small distances and how this can result in different range cover types developing adjacent to each other. This example was also included in the postclimax tallgrass prairie portion of Mixed Prairie-II herein.

32. Bigger and taller grass on deeper sand- Postclimax tallgrass prairie dominated by sand bluestem with switchgrass, Indiangrass, sideoats grama as local associate species. Other abundant grasses included little bluestem and blue grama. The dominant forb in this early summer society was fineleaf or cutleaf hymenopappus (Hymenopappus filifolius). This range vegetation was essentially edaphically determined with the relatively deep sandy soil being conducive to a more mesic range plant community than that of adjoining mixed prairie that was presented in previous (above) photographs.

Kiowa County, Kansas. Late June (early estival aspect). FRES No.39 (Prairie Grassland Ecosystem) and K-66 (Bluestem Prairie) as a postclimax or a smaller-scale edaphic climax in a region the zonal vegetation of which is FRES No. 38 (Plains Grassland). This is problematic however because there is no Kuchler unit of tallgrass prairie in FRES No. 38. Itstead this was mapped as K-62 (Bluestem-Grama Prairie). SRM 721 (Sand Bluestem-Little Bluestem [Plains]). Bluestem "Tall-Grass" Series 142.11 in Plains Grassland biotic community 142.1 of Brown et al. (1998). Sands range site. Central Great Plains- Great Bend Sand Prairie Ecoregion, 27c (Chapman et al., 2001).

34. Flat but not all short- Mixed prairie range vegetation comprised of western wheatgrass, blue grama, buffalograss, and threadleaf sedge (Carex filifolia) on the Southern High Plains. Dominance among the three dominant grasses varied from spot-to-spot . The associate species was either threadleaf caric sedge or, in some local microhabitats, red threeawn (Aristida longiseta). Other plant species present included silver bluestem, sideoats grama, and sand dropseed, but these were minor--not even approaching associate--species. For instance this was "tightland" (soil with high clay and relatively low sand content) which was far from ideal habitat for sand dropseed. Forbs were almost non-existent, but there were some plants of wavyleaf thistle (Cirsium undulatum) as for example the one "standing tall and proud" in foreground of the second of these two photographs.

It was shown and explained in the next (following) slide that overgrazing (a milder not severe degree of) had reduced absolute and relative cover of western wheatgrass so that this cool-season midgrass species was less dominant (or subdominant) compared to relative proportions (based on apparent cover) of blue grama and buffalograss. The present stocking rate appeared to be heavy enough to impede range improvement. Cattle ranges such as this typically are managed with yearlong use as this is cow-calf and not steer country. Such was the case on this range. As such, season of use was not a factor in range condition class which was easily Good. Of course, deferment (nonuse for enough time to permit some recovery of important species) during the plant growing season, especially for western wheatgrass, might handily allow for range improvement higher state of plant succession) to Excellent condition class, but this would likely not be profitable or advantageous to the ranchman (at least not in the short-run where cash flow could be more ciritcal than increased profitability farther down the ranch road).

Cheyenne County, Colorado. Early July (early estival aspect). FRES 38 (Plains Grasslands Ecosystem). K-61 (Wheatgrass-Grama-Buffalograss). SRM 609 (Wheatgrass-Grama) and/or SRM 704 (Blue Grama-Western Wheatgrass): sort of a "No Man's Land" vegetational zone between Northern and Southern Great Plains Regions (Shiflet, 1994). Mixed "Short-Grass" Series, 142,13, Plains Grassland biotic community 142.1 Cold Temperate Grassland 142 in Brown et al. (1998, p. 40). High Plains-Flat to Rolling Plains Ecoregion 25d (Chapman et al., 2006).

35. Defacto exclosure showed potential- Outside of the fence row (foreground; in front of the fence) of the western wheatgrass-blue grama-buffalograss mixed prairie range introduced in the two preceding slides (behind the fence). Where cattle grazing had been prevented on mixed prairie contiguous with (immediately adjacent to) the grazed range shown above western wheatgrass was clearly the dominant plant species with a rather sparse second layer made up of buffalograss and blue grama.

Actually there was more western wheatgrass on the grazed range than was apparent, but relatively heavy use by cattle had reduced shoot height and biomass of western wheatgrass to levels not readily seen in photographs ( least of all, wide-angle shots). Nonetheless, relative proportion of western wheatgrass (based on apparent relative cover, either foliar or basal) had been reduced by livestock grazing. This could have been years or even decades ago, but clearly the current stocking rate was high enough that recovery of the range plant community (progression along the sere by secondary plant succession) had not taken (and was not) taking place. This was an example of overgrazing, albeit a mild form from which range recovery could be fairly rapid.

Cheyenne County, Colorado. Early July (early estival aspect). FRES 38 (Plains Grasslands Ecosystem). K-61 (Wheatgrass-Grama-Buffalograss). SRM 609 (Wheatgrass-Grama) and/or SRM 704 (Blue Grama-Western Wheatgrass): sort of a "No Man's Land" vegetational zone between Northern and Southern Great Plains Regions (Shiflet, 1994). Mixed "Short-Grass" Series, 142,13, Plains Grassland biotic community 142.1 Cold Temperate Grassland 142 in Brown et al. (1998, p. 40). High Plains-Flat to Rolling Plains Ecoregion 25d (Chapman et al., 2006).

36. Across a big country- Landscape-scale views of "textbook" mixed prairie across the Colorado Piedmont. Major (dominant) species were western wheatgrass, blue grama, and buffalograss (in that overall order with local dominance varying at microsite-scale). Other, though minor, grasses included galleta, sand dropseed, and (on range from which grazing had been excluded as shown below) sand bluestem. Forbs were not to be found. There was some plains pricklypear though it was nowhere plentiful. Ranges throughout this area were just coming out of a protracted dorught of several years duration that had reached Extraordinary Drought status (greatest on Palmer Drought Index), and it had not been a real wet spring. Tough times for range life.

While this range looked rough its range condition class was high Good (maybe pushing Excellent). Scarcity of plains pricklypear and local exclusive cover of western wheatgrass attested to that fact.

Lincoln County, Colorado. Mid-July (estival aspect after dry spring). FRES 38 (Plains Grasslands Ecosystem). K-61 (Wheatgrass-Grama-Buffalograss). Sand Bluestem Variant of SRM 609 (Wheatgrass-Grama). Mixed "Short-Grass" Series, 142,13, Plains Grassland biotic community 142.1 Cold Temperate Grassland 142 in Brown et al. (1998, p. 40). Clayey Plains range site. Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion 26 e (Chapman et al., 2006).

37. Mosaics and mixes-Mixed prairie of western wheatgrass, blue grama, and buffalograss (and with very little else by way of range plant species) on the eastern Colorado Piedmont. Following visual landscape-scale perspectives in the two immediately preceding slides these two photographs portrayed the mosaic or "patchwork pattern" of local populations of the three dominant grasses (first slide) and a local "mixture" or "mini-community" of all three dominants on a localized microenvironment (second slide). Plant species diversity or richness was low on this mixed prairie range with galleta and sand dropseed along with a "splattering" of plains pricklypear pretty much rounding out the "slate of botanical players" on this expansive, semiarid "stage". Sand bluestem was a tallgrass member of the botanical lineup of the potential natural vegetation of this site, but this tallgrass species had been almost exclusively grazed out (or so weakened by overutilization as to be dwarfed survivors). (This phenomenon was the feature of the next slides.)

Stated a little differently, the mixed prairie range ecosystem featured here could be understood as a landscape of patches (a collective "quiltwork") of local, nearly exclusive populations (single species stands) of the three dominant grasses plus patches (irregular-shaped blocks) that were three-way mixtures of these dominants. These two spatial characteristics of vegetation structure, the physical arrangement of plant species on the grassland, were shown in the first and second photographs, respectively. The mixture of all three dominant grasses (midground of the first slide and entire field of the second slide) resulted in patches or blocks of two-layered vegetation with western wheatgrass comprising an upper layer and blue grama and buffalograss forming a lower layer to produce classic mixed prairie (minus a tallgrass element).

This was a remarkable structural and spatial feature given that western wheatgrass is a highly rhizomatous, sod-forming, mid-height grass that commonly forms extensive colonies from which other species are excluded. Likewise, the highly stoloniferous buffalograss is commonly an extensive-coverage, sod-forming shortgrass that establishes other-species-excluding, clonal colonies. Such sod-forming habits would seem to put the typically cespitose blue grama at a competitive disadvantage except that blue grama is the most drought-tolerant (drought "resistant) and surpases buffalograss and western wheatgrass in this regard (ie. in that decling order of drought survival; Weaver (1968, p. 187). Plus in certain range areas blue grama deviates from its bunchgrass habit to grow as "a continuous sod--or only ptches of sod interrupted by other grasses depending upon the available soil moisture" (Weaver, 1968, p. 200). In fact, blue grama typically has a sod-forming habit dWhile "[b]lue grama is much more drought resistant than buffalograss" recovery from drought is greater--as is tolerance to close grazing--for the stoloniferous buffalograss (Weaver and Albertson, 1956, ps.33, 37, 79, 103-104, 133) Weaver and Albertson (1956, p. 149) remarked that the "intermingling" of these two shortgrass species had been a subject of "great Interest". Such "intermingling" is one of the first plant patterns (structural characteristics) to catch the rangeman's eye upon viewing shortgrass and mixed prairie ranges. These two chlorocoid grasses have been co-dominant "pardners" through many a drought over a nearly countless span of evolutionary time.

Apparently periodic drought combined with grazing permits these two shortgrass species to compete with western wheatgrass, the taller and more moisture-requiring midgrass. For whatever combinations of factors are at work, these three grasses sometimes grow tiller by stolon in unique mixtures on Great Plains grasslands.

It would seem all that was lacking from this horizon-to-horizon mixed prairie range was a tallgrass species. Please scroll down.

Lincoln County, Colorado. Mid-July (estival aspect after dry spring). FRES 38 (Plains Grasslands Ecosystem). K-61 (Wheatgrass-Grama-Buffalograss). Sand Bluestem Variant of SRM 609 (Wheatgrass-Grama). Mixed "Short-Grass" Series, 142,13, Plains Grassland biotic community 142.1 Cold Temperate Grassland 142 in Brown et al. (1998, p. 40) Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion 26 e (Chapman et al., 2006).

38. Ready made exclosure for range comparisons- The highway right-of-way next (adjacent) to the range shown and described in the two immediately preceding sets of slides and captions made for a handy comparison of mixed prairie vegetation inside and outside the cattle range (enclosure and exclosure, respectively). Time for a quick culture and history lesson. In Colorado the state has the legal obligation to maintain fences along its highways. The result is--and notwithstanding snide remarks about the ineffectiveness and inefficiency of government--that rights-of-way on roadways in the Centennial State are remarkably free of would-be breechy and fence-crawling strays. In this way, outer fencerows, especially wide ones, make convenient exclosures from which trrveling rangemen can compare vegetation on largely ungrazed (or lightly grazed by native ungulates) tracts to those grazed by livestock at varying stocking rates, seasons, frequencies, etc.

Such a comparison--even a quick one while barrelling down the road like a bat outa you know where--as afforded for the mixed prairie example featured here was so revealing that even the hypothetical chauffeur could fit the "missing species" (at least if he knew his grasses). The right-of-way vegetation was overwhelmingly western wheatgrass with noticeably less cover, density, etc. of blue grama and buffalograss. Although these two shortgrass species were present in the "exclosure" as on the cattle-grazed range (the "enclosure") shown in the background, "exclosure" shortgrasses were more associates than species that shared dominance with western wheatgrass. The "three-way mixture" of the "exclosure" was not so evenly "split" among grass species as on the cattle range (compare these two slides to the second onein the preceding set).

The real revelation, however, was the presence of sand bluestem (Andropogon hallii)--albeit not of great cover--in the "exclosure". Sand bluestem plants were the comparatively large herbaceous bunches present in both of these photographs. A tallgrass species was present on mixed prairie that had been protected from heavier grazing whereas the tallgrass was either missing from or had been grazed to depauperate dimensions on the cattle range. Viewers should recall from above that this general area had been in Extraordinary Drought (Palmer Drought Index) for at least the last two growing seasons.Grassland vegetation was recovering from that stress. Sand bluestem plants were not at their characteristic heights of four to six or more feet, nor would they be at this point in the current growing season even under "normal conditions".

The clumps of sand bluestem seen here had been through the previous autumn, winter, and spring seasons with any weathering and decomposition that took place then. In contrast, most of the shoots of the cool-season western wheatgrass were those produced in the current spring through early summer period. In fact, many of the wheatgrass shoots were still alive (green color) whereas all visible shoots of sand bluestem were from the previous year(s) with this year's shoots still largely covered by older shoots.

The potential natural vegetation, the climax for this range site, was mixed prairie with tallgrass, midgrass, and shortgrass species which formed three layers, the tallgrass layer of which would more than likely be sporadic or discontinuous in structure. The two-layered mixed prairie with less cover of the midgrass component (western wheatgrass) compared to that of shortgrasses in protected vegetation, and without a detectable tallgrass component, was a grazing disclimax. Even at that, however, the mixed prairie cattle range was probably in Good (certainly high Fair) range condition class. It was possible that sand bluestem was an ice cream species on this range site or, at least, under present management which possibly could be interpreted as wise use management. An ice cream species was defined by the Society for Range Management (Kothmann, 1974) as" "An exceptionally palatable species sought and grazed first by livestock and game animals. Such species are usually overutilized under proper grazing." Even if ice cream species are not "exceptionally palatable" there can be other reasons why they are difficult to maintain on the range even under proper grazing management. For example, taller-growing species are often more vulnerable to defoliation due to location and height of main growing point (apical meristem) that is more easily or apt to be lost during grazing. Sand bluestem does not elevate its apical meristem until later in the season, but sooner or later its growing point is going to tower over those of mid- and shortgrass species. And, as it happens, sand bluestem is one of the more palatable native grasses (Phillips Petroleum Company, 1963; Bryoles, 2004). The author was not familar with any preference studies that compared sand bluestem to the other major grass species on this mixed prairie range.

Regardless, sand bluestem on this range type and range site was also an indicator species: "(1) Species that indicte the presence of certain enviromental conditions, seral stages, or previous treatments. (2) One or more plant species selected to indicate a certainl level of grazing use" (Kothmann, 1974). Sand bluestem would fit both of these situational definitions.

Lincoln County, Colorado. Mid-July (estival aspect after dry spring). FRES 38 (Plains Grasslands Ecosystem). K-61 (Wheatgrass-Grama-Buffalograss). Sand Bluestem Variant of SRM 609 (Wheatgrass-Grama). Mixed "Short-Grass" Series, 142,13, Plains Grassland biotic community 142.1 Cold Temperate Grassland 142 in Brown et al. (1998, p. 40) Clayey Plains range site. Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion 26 e (Chapman et al., 2006).

39. Mixed prairie used as stocker range- Steers (Bos taurus) grazing mixed prairie dominated by sand dropseed with blue grama and needle-and-thread well distributed throughout while western wheatgrass dominated small swales at local scale. Most common forb was Louisiana sagewort or Louisiana mugwort. The relatively tall, dark green stalks in left background were longstyle rush (Juncus longistylis) growing in a normally seepy depression. There were no seeps-- or much moisture anywhere-- in this spring and summer of 2002, the single driest year to-date in Colorado weather records. The remarkable ability of range plants to survive and even grow in extreme drought was illustrated by this example of plains grassland on the semiarid High Plains under devastating drought.

Lincoln County, Colorado. Estival aspect (as modified by drought), June. FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 715 (Grama-Buffalograss, sand dropseed variant). Mixed "Short-Grass" Series of Brown et al. (1998). Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion, 26e (Chapman et al., 2006).

40. Pristine mixed prairie near its western boundary - Climax vegetation of western wheatgrass, blue grama, and needle-and-thread with abundant shrub cover of fourwing saltbush (Atriplex canescens) so that this mixed prairie-shrub community could be interpreted as either grallsnad or a grass-shrub savannah. This was an example shrub-mixed prairie "mint condition" (Excellent range condition class) that developed near the Front Range of the Rocky Mountains. These "photo-plots" of a type of mixed prairie at its zenith furnished a rare sample of what one imagines the Indians and the first "white intruders" found at the western margin of teh Great Plains. Two other major midgrasses in this range plant community were sand dropseed and, at lesser cover and frequency, plains lovegrass. Forbs were absent for all practical purposes.

This climax range vegetation was not high in biodiversity, either as to species richness, life (growth) forms, vegetational layers, or physiogonomy, but it represented the ultimate mainfestation of mixed prairie on the western Great Plains. For whatever reason(s) this unfenced range was not grazed by livestock though obviously abundant wildlife species including black-tailed jackrabbit (Lepus californicus), pronghorn (Antilocapra americana), and mule deer (Odocoileus hemionus) found this virgin condition range to be a Garden of Eden or Mecca. LIght grazing by wildlife (and insects) was responsible for the lack of substantial utilization and the outstanding vegetational manifestation of this rangeland cover type. Light degree of use of the herbage of this range plant community was shown in the succeeding photograph.

Washington County, Colorado. Late June, late vernal to early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). No unit in Brown et al. (1998). High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

41. Composition of mixed prairie on its western boundary - "Photo-quadrant" of the western wheatgrass--blue grama--needle-and-thread--fourwing saltbush mixed prairie savanna described for the immediately preceding set of potographs. Sand dropseed (largest grass clumps as in center-right of this photograph) was featured here so illustrate the light degree of use (by antelope and/or mule deer) of this range herbage. Fourwing saltbush was not included in this view.

Washington County, Colorado. Late June, late vernal to early estival aspect. FRES No. 38 (Plains Grassland Ecosystem).K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). No unit in Brown et al. (1998). High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

42. Floodplain on the plains- Lowland mixed prairie range of alkali sacaton (Sporobolus airoides) and galleta (Hilaria jamesii) on part of the greater floodplain of the Arkansas River in the Southern Great Plains.Western wheatgrass was a distant associate species while blue grama and buffalograss were frequent enough to remind those who, like this photogtrapher, were enthralled by the granduer of these midgrasses that shortgrasses were more commonly the dominant or associate species of grasslands on these semiarid High Plains..

This part of the Southern High Plains was in the seventh or eighth straight year of a devestating drought that had reached the category of Exceptional (highest drought rank on the Drought Severity scale; corresponding to Palmer Drought Index of -5.0). A recent local shower combined with deeper (hence, less dry) soil had permitted greenup of the co-dominant alkali sacaton and galleta. Early morning light on greening grass being properly grazed by cattle was captured in these photographs to tell of the dawning of another day.

Crowley County, Colorado. Late June; late vernal to estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No Kuchler (1964, 1966) unit at the restricted spatial scale of this climax vegetation. SRM 712 (Galleta-Alkali Sacaton). Not a very descriptive (precise) unit in Brown et al. (1998, p. 40), but Mixed "Short-Grass" Series142.13 of Plains Grassland biotic community 142.1 comes closest. Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion, 26e (Chapman et al., 2006).

43. Co-dominants on flood mixed prairie- Alkali sacaton and galleta dominated a bottomland or lowland mixed prairie on the greater floodplain of the Arkansas River in the High Plains. Western wheatgrass qualified--though barely--as the associate species. Blue grama and buffalograss were very limited but on local microsites contributed a shortgrass component to an otherwise exclusively midgrass mixed prairie. A recent, highly localized "shower of blessing" in an area caught in the clutches of an Exceptional drought afforded an opportunity for drought-dormant grass to initiate spring growth as shown in these early morning shots on the first full day of summer. Diffuse light (especially in the second of these photographs) of early morning and the peak period of grazing animal activity highlighted the promise of a new day on the drought-prone semiarid High Plains.

The presence of this much dead herbage in the eighth straight year of drought (culminating in the highest drought severity score) presented to students an example of outstanding stewardship of the range: light grazing being practiced to save enough feed for cattle and pronghorn in drought is wise use management of grazing land, and basic common sense. When rain comes--as it always does sooner or later--proper grazing permits grass and other range plants to recover faster and reduces the likelihood of severe range depletion by retrogression induced by drought. In the long run nothing is gained by assisting drought to degrade the range plant community and, perhaps, inflict greater damage on range ecosystems through soil erosion.

This was beautiful range skilfully and wisely managed under the most trying of times. Drought is, over time, the greatest risk (including blizzards) inherent in ranching in the semiarid zone.

Crowley County, Colorado. Late June; late vernal to estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No Kuchler (1964, 1966) unit at the restricted spatial scale of this climax vegetation. SRM 712 (Galleta-Alkali Sacaton). Not a very descriptive (precise) unit in Brown et al. (1998, p. 40), but Mixed "Short-Grass" Series142.13 of Plains Grassland biotic community 142.1 comes closest. Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion, 26e (Chapman et al., 2006).

44. Galleta on the upper Arkansas- Representative plants on the greater floodplain of the Arkansas River. It was explained above that in minst of prolongued drought this relatively small area had received "showers of blessing" such that ranges therein had growth and plant productivity typical of an "average year". Galleta was grwoing in association with alkali sacaton.

Crowley County, Colorado. Late June: peak anthesis.

45. Anthesis in inflorescence of galleta- The inflorescence of Hilaria species is interpreted as a "...dense, bilatral spike, the spikelets in clusters of three at each node of a zigzag rachis" (Gould, 1975, p. 366). Of these three spikelets the two lateral ones are staminate and two-flowered while the central spikelet is perfect and one-flowered.

Crowley County, Colorado. Late June: peak anthesis.

46. Alkali sacaton on the upper Arkansas- On much of the greater floodplain (not so much the bank or first terrace) of the Arkansas River alkali sacaton and galleta form broad expanses of mesic plains grassland. These are examples of alkali sacaton growing on that range (described above). Alkali sacaton is one of the higher herbage-yielding native grasses. Floodplain range sites are also have extremely high production-potential. A combination of alkali sacaton (with or without other species like galleta) and the high water content of soils on floodplain or overflow sites makes for high herbage yields in the semiarid precipitation zone.

Crowley County, Colorado. Late June: end of (and just past) anthesis.

47. Panicles and spikelets of alkali sacaton-Sahpe of panicles of alkali sacaton vary but toen to have a somewhat pyramid-shape. Spikelets have one floret with an awnless lemma. The purple-tinged glumes and lemmas of the spikelets shown in the second photograph are typical of this species.

Crowley County, Colorado. Late June: end of and just past anthesis.

48. Coming off the upland- A slightly lower "lay of the land" resulted in a consociation of galleta on the Colorado Piedmont that developed as a transition between the slightly higher and drier upland of blue grama-galleta range (SRM 705) and the lower, more mesic galleta-alkali sacaton flats (SRM 712). This was a general catena arrangement of range vegetation. A catena or toposequence is a spatial sequence of various soils (series or associations) of similar age, parent material, and climate occurring along a slope, drainage, etc. such that topographic relief was the primary soil forming factor (Soil Science Society of America, 2001). There are different range sites and/or types associated with the different soils so that range vegetation varies mostly due to edaphic differences. (Seee note on organization below.)

There were scattered plants of blue grama and even western wheatgrass along with widely scattered cholla cactus in this mid-slope range plant community. Clearly, however, this range vegetation was almost exclusively one of a population of galleta.

This range was in its third year of Extraordinary drought (the worst or "highest" category on the Palmer Drought Severity Index). The range had been destocked of cattle for the better part of the last two years. This had permitted preservation of this priceless natural pasture. The intelligent rangeman who owned this land had the wisdom to cut his losses and sell off some and move other cattle rather than foolishly destroy his range and go broke trying to provide adequate survival feed under drought conditions to which there was to near end.

Recent light rains had been enough to cause some shoots of galleta to come out of drought dormancy and "dare to show a little green". When regular rains return as they always do (sooner or later) this range operator will be in fine shape to once again raise beef profitably on this productive rangeland in the harsh semiarid region of the southern Great Plains.

Pueblo County, Colorado. Late June (early estival aspect in extraordinary drought). FRES No. 38 (Plains Grassland Ecosystem). No Kuchler (1964, 1966) unit at the restricted spatial scale of this climax vegetation. SRM 712 (Galleta-Alkali Sacaton). Not a very descriptive (precise) unit in Brown et al. (1998, p. 40), but Mixed "Short-Grass" Series142.13 of Plains Grassland biotic community 142.1 comes closest. Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion, 26e (Chapman et al., 2006).

49. Dry, but mighty productive on lowland range An alkali sacton flat that persisted--under proper grazing management--during three years of Extraordinary drought. This consociation of alkali sacaton developed on a broad valley in the Colorado Piedmont section of the Great Plains province. It had been destocked of cattle a consequence of the drought.

Students should take note of the quantity of herbage (biomass or standing crop) remaining. This owner was both good stewart of the range and his cattle. He had faced the reality that it would not pay in the longrun to destroy his remarkably productive range and suffer terrific outgo of cash and/or capital to hopelessly try to retain cattle through the "bottomless pit" of survival feeding.

Recent light showers had been sufficient to bring about some green growth from alkali sacaton plants that had been given the respect and proper husbandry benefitting such a valuable forage resource.

Otero County, Colorado. Late June (early estival aspect in extraordinary drought). FRES No. 38 (Plains Grassland Ecosystem). No Kuchler (1964, 1966) unit at the restricted spatial scale of this climax vegetation. SRM 712 (Galleta-Alkali Sacaton). Not a very descriptive (precise) unit in Brown et al. (1998, p. 40), but Mixed "Short-Grass" Series142.13 of Plains Grassland biotic community 142.1 comes closest. Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion, 26e (Chapman et al., 2006).

Organization note: upland range vegetation dominated by 1) blue grama (a consociation of that species) with minor amounts of buffalograss and western wheatgrass and 2) co-dominated by blue grama and galleta with cholla cactus as the associate species had developed in close proximity to the two more lowland range types presented in the two immediately preceding photograph-caption sets. Examples of these adjoining range plant communities (rangeland cover types) were included farther below in this chapter under the section, Shortgrass Prairie Sampler.

The viewer can go there and find these other two range communities by a corresponding organization note placed there and then finding the examples form Huerfano and Pueblo Counties, Colorado. These taken together with the ones just shown will present the catena arrangement of four distinctive range dominance types.

This organization was used in order to keep the different range types together rather than organize different range types based on geographic location (ie. it was vegetation not spatial proximity and pattern that was basis of arrangement in Range Types of North America).

50. Mixed prairie (estival aspect) in Loess Hills of southwestern Nebraska- Geologic erosion has created networks of "canyons"deep enough to produce north and south slope aspects as shown here (N slope on left side of canyon). Species vary from big and little bluestem to blue and hairy grama and buffalograss. Western wheatgrass forms exclusive single species colonies carpeting floors of canyons. Some sand sagebrush (Artemisia filifolia) on south slopes along with Yucca glauca. Some eastern cottonwood and plum (Prunus sp.) thickets in draws draining into canyons.

Hays County, Nebraska. Late July (estival aspect). FRES No. 38 (Plains Grasslands Ecosystem). Blend of K- 61 (Wheatgrass-Gramagrass-Buffalograss) and K-62 (Bluestem-Gramagrass Prairie). SRM 604 (Bluestem-Grama Prairie) or SRM 709 (Bluestem-Grama). Western High Plains- Moderate Relief Tablelands Ecoregion, 25c (Chapman et al., 2001).

51. Landscape of the Loess Hills- Range vegetation and general land form of the Arikaree Breaks in extreme northwestern Kansas. The range plant community was mixed prairie of the western wheatgrass-buffalograss-blue grama type. Dominance of these three grass species varied locally as to microsite. Sand dropseed was the most abundant associate species. Plains pricklypear was the major (generally the only) woody species. Buffalograss was at peak anthesis.

The Arikaree Breaks are a narrow strip (roughly three miles wide) of badlands that formed from wind-blown loess to the north of the valleys of the Arikaree and Republicn Rivers. These so-called "badlands" ("breaks" is a much more accurate description) are not particularily dramatic compared to better-known and more spectacular badlands and the "canyons" are not as spectacular as those located just to the north (see immediately above), but they are distinct and distinctive. The rangeland vegetation of the Arikaree Breaks afforded a good example of mixed prairie with a prominent midgrass and shortgrasses. The example shown here lacked a tallgrass component, little bluestem being lacking from this plant community.

Cheyenne County, Kansas. Mid-June (late vernal aspect). FRES No. 38 (Plains Grasslands Ecosystem). K- 61 (Wheatgrass-Gramagrass-Buffalograss). SRM 609 (Wheatgrass-Grama). Mixed "Short-Grass" Series, 142,13 of Plains Grassland biotic community 142.1 of Cold Temperate Grassland 142 of Brown eta al (1998, p. 40). Western High Plains- Moderate Relief Rangeland Ecoregion, 25c (Chapman et al., 2001).

52. Shortgrass sod on loess land- Local sward of blue grama (two clumps or tufts in both photographs) and buffalograss (most of vegetational cover in both slides) that made up almost all of the shortgrass component of the Loess Hills mixed prairie range introduced in the two immediately preceding photographs of the Arikaree Breaks. Western wheatgrass, the dominant midgrass and sand dropseed, the associate midgrass, comprised this tallest layer of this semiarid grassland. Plains pricklypear (Opuntia polycantha) was the sole woody plant species in this range vegetation, but it added a shrub component to the grassland. The most readily observed representative of plains pricklypear was that blooming in right-center foreground of first slide and the slightly smaller plant left-center midground of second slide.

Cheyenne County, Kansas. Mid-June (late vernal aspect). FRES No. 38 (Plains Grasslands Ecosystem). K- 61 (Wheatgrass-Gramagrass-Buffalograss). SRM 609 (Wheatgrass-Grama). Mixed "Short-Grass" Series, 142,13 of Plains Grassland biotic community 142.1 of Cold Temperate Grassland 142 of Brown eta al (1998, p. 40). Western High Plains- Moderate Relief Rangeland Ecoregion, 25c (Chapman et al., 2001).

53. God's grain crop in the Loess Hills- Local population of western wheatgrass tillers on the mixed prairie range described immediately above that was in the Arikaree Breaks portion of the Loess Hills of northwest Kansas (Cheyenne County). Much of the adjoining land that was once mixed prairie was converted to cropland, especially for wheat which is one of man's major grain crops. Western wheatgrass was God's grain long before man arrived.

Mid-June; phenological stage of western wheatgrass varied from anthesis to soft-dough state of grain.

54. Patchwork of mixed prairie range sites form clay pans to deeper sand dominated locally by an array of species from sand dropseed (Sporbolus cryptandrus) to western wheatgrass, sideoats grama, silver bluestem (Andropogon saccharoides= Bothriochloa saccharoides).

Otero County, Colorado.July (estival aspect). FRES No. 38 (Plains Grasslands Ecosystem). K-61 (Wheatgrass-Gramagrass-Buffalograss). SRM 604 (Bluestem-Grama Prairie variant). Southwestern Tablelands- Piedmont Plains and Tablelands Ecoregion, 26e (Chapman et al., 2006).

55. Mixed prairie in Texas Rolling Red Plains- The diverse range plant community presented here included tallgrass, mid-grass, and shortgrass species along with shrubs and a few composite forbs. Little bluestem was the dominant with sideoats grama and silver bluestem associates. Buffalograss grew in the interspaces among the cespitose tall- and midgrass species. Vine mesquite dominated the draws except in the thickets of wild plumb (Prunus sp.). There were traces of sand bluestem and sand sagebrush as postclimax components. Skunkbush sumac and soapweed (Yucca glauca) were infrequent but dominated some microsites. Sand and plains lovegrasses grew sparingly.

Gray County, Texas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Gramagrass Prairie). SRM 709 (Bluestem-Grama). Mixed "Short-Grass Series" of Brown et al. (1998). Central Great Plains- Red Prairie Ecoregion, 27h (Griffith et al., 2004).

57. Rolling Red Plains rangeland as seen by the redman- Although this land is technically in the High Plains section of Great Plains physiogrphic province it is in the an example of Rolling Redlands mixed prairie range in climax condition. Little bulestem is the sole dominant while sideoats grama and silver bluestem are associates. Rich species diversity prevails however with numerous other grass speceis including hairy and blue grama, sand dropseed, buffalograss, Indiangrass, galleta, and curly mesquite present on various microsites. Wild alfalfa was also common as were several composites The only shrubs were sand sagebrush and soapweed yucca.

Wheeler County, Texas. June, early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). SRM 709 (Bluestem-Grama Prairie). Mixed "Short-Grass" Series of Brown et al. (1998).Central Great Plains-Red Prairie Ecoregion 27h (Griffith et al,. 2004). Central Great Plains- Red Prairie Ecoregion, 27h (Griffith et al., 2004).

58. Good range gone bad- This range vegetation was conterminous with that featured in the preceding slide. In fact part of that climax condition mixed prairie range was visible in the background of this slide. Range sites were the same. Severe disturbance(s) that could have included previous plowing, overgrazing, wrongly timed or poorly manage fires, etc. (more than likely God in His Heaven only knows what) degrated this range vegetation. This is now largely a sand sagebrush disclimax. Soapweed yucca had also increased condiderably. Perennial grasses were rare and largely replacecd by the Eurasian annual grass, Japanese chess (Bromus japonicus). Annual broomweed (Gutierrezia draculoides) was also common.

Wheeler County, Texas. June, early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). K- 62 (Bluestem-Grama Prairie).SRM 709 (Bluestem-Grama). Mixed "Short-Grass" Series of Brown et al. (1998). Central Great Plains-Red Prairie Ecoregion 27h (Griffith et al., 2004). Central Great Plains- Red Prairie Ecoregion, 27h (Griffith et al., 2004).

59. Landscape-scale view of plains and mesa grassland (High Plains mixed prairie ecosystem)- This landscape-scale "shot" caught landform, physiogonomy and structure of vegetation, and typical atmospere on a "plains morning" of a semiarid Great Plains grassland. Blessings of recent rains allowed this superb example of it's range type (Excellent range condition class) to portray it's natural potential at this season. Although generally thought and spoken of as "short grass country" the climax vegetation of this range site (and general range region) is a classic mixed prairie with three pronounced herbaceous layers (short-, mid-, and tallgrass species often with forbs in each) plus a shrub layer (here represented by cholla cactus, soapweed yucca, and/or sand sagebrush on coarser textured soils).

At this early summer stage of phenological development (and delayed growing season precipitation) the tallgrass component was not conspicuous but it was well-represented by upland switchgrass. Buffalograss, the associate species, and small patches of curly mesquite comprised most of the shortgrass layer while blue gramma and galleta, the community dominants, made up most of the vegetation and the predominant mid-grass physiogonomy. (This will be more pronounced for blue grama when it soon sends up sexually reproductive shoots.) Patches of western wheatgrass along with sideoats grama and sand dropseed contribute further to the mid-grass and mixed prairie appearance. Forbs were limited, and mostly composite species at pre-bloom stages. All-in-all: pristine!

Oldham County, Texas. Early estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-58 (Gramagrass-Buffalograss). SRM 705 (Blue Grama-Galleta).Grama "Short-Grass" Series of Brown et al. (1998). Southwestern Tablelands- Semiarid Canadian Breaks, 26d (Griffith et al., 2004).

60. Sward of climax blue grama-galleta mixed prairie grassland- Detail photograph of the estival-aspect herbaceous vegetation of the Excellent condition mixed prairie form of plains and mesa grassland presented in the immediately preceding slide. Light grazing by cattle and delayed phenological development due to delayed rains were reflected in appearance of grass, but co-dominant galleta and blue gramma along with buffalograss as the associate species were obvious. Populations of these species were presented at community scale in the next slide.

Oldham County, Texas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-58 (Gramagrass-Buffalograss). SRM 705 (Grama-Galleta). Grama "Short-Grass" Series of Brown et al (1998). Southwestern Tablelands- Semiarid Canadian Breaks, 26d (Griffith et al., 2004).

61. Mixed prairie plains and mesa grassland- This is a community scale scene of semiarid steppe in the southern High Plains. This is the High Plains section of the Great Plains physiographic province known also as the Llano Estacado ("Staked Plains"). Here is another view of the cattle range shown in the two immediately preceding slides. Local populations or colonies of the different plant species formed a mosaic or "patchwork" expression of vegetation. Easily discernable species were cholla, galleta (grass with light gray inflorescences in right foreground), buffalograss (the shortest grass and with spots of bare soil interspersed within), and blue gramma (the grass with the darkest green hue and comprising most of the understorey in the area beginning at right background where cholla cactus was the aspect dominant).

Oldham County, Texas. Estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-58 (Gramagrass-Buffalograss). SRM 705 (Grama-Galleta). Grama "Short-Grass" Series of Brown et al. (1998). Southwestern Tablelands- Semiarid Canadian Breaks, 26d (Griffith et al., 2004).

62. Mesa and plains grassland— Shortgrass plains or shortgrass form of mixed prairie depending upon interpretation and which classification of vegetation types is used. Besides blue grama and buffalograss, galleta (Hilaria jamesii) rounds out the three dominant species. Several species ofthreeawn such as Aristida purpurea and A. longiseta are present but mid-grasses like western wheatgrass, sideoats grama, and siver bluestem are absent. Cholla (Opuntia imbricata) lends a savanna-like aspect to this shortgrass country and serves as an emergency feed source in drought if spines are burned off with propane burners. Peak estival aspect, June. Quay County, New Mexico. FRES No. 38 (Plains Grasslands Ecosystem). K-58 (Gramagrass-Buffalograss). SRM 502 (Grama-Galleta). Grama "Short-Grass" Series of Brown et al. (1998). Southwestern Tablelands- Semiarid Canadian Breaks Ecoregion, 26d (Omernik and Griffith, 2006).

63. High Plains Breaks range- This was one of many varied forms of the Breaks ranges site that is widely distributed on the shortgrass and mixed prairie ranges of the High Plains (Llano Estacado). These grassland communities were entitled and described by Dick-Peddie (1993, ps. 104-106, 113-115) as Plains-Mesa Grasslands. Breaks are typically a grassland range site (again, of various forms), but some expressions of this generic range site are climax shrublands (see Breaks Scrub under Miscellaneous Shrublands). The climax grassland range breaks seen here are of mixed prairie High Plains grassland range having a shrub component consisting of skunkbush or fragrant sumac (Rhus trilobata= R. aromatica), soapweed yucca, broom snakeweed (Gutierrezia sarothrae), and fragrant mimosa (Mimosa borealis) in that order. The grassland vegetation shown here was the Galleta-Indian Ricegrass-Needlegrass Series (Hilaria jamesii-Hymenoxix oryzoides-Stipa neomexica-Mixed Forb Species) of Dick-Peddie (1993, p. 110).

Galleta and New Mexico feathergrass (=needlegrass) were the dominants; Indian ricegrass was present in small amounts as an indictor species and, perhaps, as a relict species. Other common grasses included blue, sideoats, and hairy gramas; buffalograss; silver bluestem, and threeawns (of the Aristida purpurea complex).

Major forb species growing on this specific range were featured immediately below following photographs of skunkbush sumac.

Quay County, New Mexico. June, estival aspect. FRES No. 38 (Plains Grassland Ecosystem). None of the Kuchler units comes close: this omission indicated an incomplete classification by Kuchler (1964, in Garrison et al., 1977) as documented by the more comprehensive list of climax Plains-Mesa Grassland communites provided by Dick-Peddie (1993, ps. 110-111). Likewise there was no SRM (Shiflet, 1994) rangeland cover type that accurately described this rangeland vegetation that was clearly covered by the Galleta-Indian Ricegrass-Needlegrass Series of Dick-Peddie (1993, p. 110). This could be interpretedas as one of "many variations" occurring in the SRM 716 (Grama-Feathergrass) rangeland cover type. A form or subunit of Mixed "Short-Grass" Series of Brown et al. (1998). Southwestern Tablelands- Semiarid Canadian Breaks Ecoregion, 26d (Omernik and Griffith, 2006).

.

69. Prairie bluets (Houstonia nigricans= Hedyotis nagricaus)- OK, another one the taxonomists are rilin' the herd over. Of course, this little High Plains forb is not worth much fuss, but it did add biodiversity (that catch-all virtue of the "natural crowd") on the range and the fraternity of Good Rangemen and True was proud to accept approvial where it could get it.

This range forb is in the madder family (Rubiaceae). Quay County, New Mexico. June.

73. Almost a tallgrass type on the High Plains- This little bluestem-dropseed-feathergrass mixed prairie approached the physiogonomy and had a species composition that resembled that of tallgrass prairie. This was an example of several rangeland cover types recognized by the Society for Range Manageament (Shiflet, 1994) as developing on the Canadian-Pecos Rivers drainage portion of the High Plains portion of the Southern Great Plains. Tallgrass species were represented by little bluestem an dgiant dropseed (Sporobolus giganteus) midgrasses included New Mexico feathergrass, the dominant (at least the aspect dominant), sand dropseed, and sideoats grama; while the shortgrass species of buffalograss and blue and hairy grama were common on local "spots". Relict plants of spike dropseed (Sporobolus contractus) were found on the outside of the fencerow which seemed to "clinch" this rangeland cover type.

It was possible that continued summer grazing of this specific range for a number of years had favored New Mexico fethergrass over the climax warm-season little bluestem and dropseed species. Also, abundant fall and winter moisture contributed to one of the best crops of fethergrass in recent memory such that this cool-season climax member of the community had been extremely productive. Finally, this scene in early summer was prior to the summer rainfall pattern of this climate so that there was very little current growth of the dropseeds and little bluestem.

Shrubs included soapweed yucca and broom snakeweed, but cover and densty of these species was not in excess of what would be expected on high Good range condition class which was the apparent successional status of this properly managed range. There were almost no forbs.

Quadalupe County, New Mexico. June. FRES No. 38 (Plains Grassland Ecosystem). There was no appropriately descriptive Kuchler unit. Nor did Dick-Peddie (1993, ps. 110-111) list a Plains-Mesa Grassland series that was consistent with the published SRM (Shiflet, 1994) description. This was a "tightland", New Mexico feathergrass variant of SRM 708 (Bluestem-Dropseed). Finally there was not an appropriate series offered by Brown et al. (1998). Southwestern Tablelands- Central New Mexico Plains Ecoregion, 26o (Omernik and Griffith, 2006).

74. Feathergrass-Indian ricegrass range- This Plains-Mesa Grassland had a species composition different from any series presented by Dick-Peddie (1993, ps. 104-106, 110-111), but this specific range plant community was part of the Grama-Feathergrass series.. New Mexico feathergrass was dominant and Indian ricegrass was the associate. Blue and black grama were distant "also rans". Soaptree yucca (Yucca elata) and Bigelow sagebrush (Artemisia bigelovii) were localized in microsites and present in a wide pattern of dispersion. This range vegetation whown here was commonly present on uplands at higher elevation above black grama-dominated plains both of which were in the Sacramento section of the Basin and Range physiographic province.Successional statue was not known, but range condition was probably in Good class.

Black grama-grassland range that was below the range vegetation viewed here was interpreted as being in semidesert grassland and was treated in that chapter in this publication. Higher elevation with commensurate cooler ambient temperatures and greater, more effective soil moisture allowed extension of Great Plains grassland, Dick-Peddie (1993, 104-106, 110-111) into the Basin and Range Region.

FRES No. 38 (Plains Grassland Ecosystem). Smaller unit of range vegetation as part of K-57 (Grama-Needlegrass-Wheatgrass). One of "many variations" of SRM 716 (Grama-Fethergrass). No appropriaate series in Brown et al. (1998). Technical mini-editorial: The list of series under Plains Grassland 142.1 (Brown et al., 1998, p. 40) is much too general to be of much use. In comparison Semidesert (Chihuhuan) Grassland 143.1 has 2/5ths again as many series units and the latter is far less diverse in range types, plant species, soils, topography, climate, etc. than the Plains Grassland. Southwestern Tablelands- Central New Mexico Plains Ecoregion, 26o (Omernik and Griffith, 2006).

Lincoln County, New Mexico. June.

77. Xeric expression or form of Great Plains grassland- Range vegetation that was Great Plains-mesa mixed prairie-semidesert (Chihuhuan) grassland transition, a semiarid low mountain grassland. This picturesque foothill range was in the famous Wild Rose Pass in the Arkansas Mountains at an approximate elevation of 4300 feet. This was an example of an "island" of Great Plains grassland within the Trans-Pecos Basin and Range Region resulting in characteristic and indicator species from the drier semidesert grasslands (located to the west and south) growing with the more common and abundant plains-mesa mixed prairie. This range was somewhat degraded (high seral stage community just prior to climax), but it was an approximation of the potential natural vegetation. Blue grama was the general dominant with black grama and sideoats grama associate species. Hairy grama, cane bluestem (Andropogon barbinodis= Bothriochloa barbinoidis), sand dropseed, plains bristlegrass (Setaria leucopila), buffalograss, tanglehead (Heteropogon contortus), and threeawns (Aristida purpurea complex) were also present. Dominant forb was Louisiana sagewort (Artemesia ludoviciana). Shrubs included alligator juniper (Juniperus deppeana), Havard agave (Agave havardii), pricklypear and cholla cactus (Opuntia spp.), splitleaf bricklebush (Brickellia laciniata) and whitethorn acacia (Acacia constricta).

This range type was one of "many variations" of SRM 706 (Blue Grama-Sideoats Grama) or SRM 707 (Blue Grama-Sideoats Grama-Black Grama), or perhaps more descriptively, as a transition range type between SRM 706 or SRM 707 and the mixed grass hillside semidesert grassland, the Grama-Andropogon- Trichachne community of Whitfield and Beutner, 1939, p. 35-36). The latter was covered under Semidesert Grassland. Presence of Agave and Acacia species as well as the high density and cover of cane bluestem in favorable microhabitats were indications more typical of vegetation in the Basin and Range province.

Jeff Davis County, Texas. June, early estival aspect; current growth mostly of shrubs). FRES No. 38 (Pains Grassland). No appropriate Kuchler (1964, in Garrison et al., 1977) unit or Brown et al. (1998) series. Soil Conservation Service (Soil Survey, Jeff Davis County, Texas, 1972) Igneous Hill and Mountain range site in the Mountains Grassland vegetation. Isolated unit of High Plains- Llano Estacado Ecoregion 25i within Chihuhuan Deserts- Low Mountains and Bajadas Ecoregion 24c.

78. Interloper Great Plains-mesa grassland in Trans-Pecos Basin and Range Region- Detail of richly diverse range vegetation on Wild Rose Pass in Arkansas Mountains of the Basin and Range province. The range vegetation on this vlow mountain mixed prairie was generally a grama-bluestem transition range type: SRM 706 (Blue Grama-Sideoats Grama) or SRM 707 (Blue Grama-Sideoats Grama-Black Grama)of the Southern Great Plains with floristic and structural elements from the semidesert mixed-grass mountain grassland mixed grass of the Chihuhuan Basin and Range Region. This latter range type was treated in the chapter, Semidesert Grassland.

Plant species readily distinguished included Louisiana sagewort (= mugwort), conspicuous silver foliage in second slide, whitethorn acacia, Havard agave, and alligater juniper. Blue grama was the dominant with sideoats grama and black grama associates. Cane bluestem was scattered widely but sparse and this was taken as an indicator species of semiarid mountain grasslands to the south and west. Other Gramineae were listed in the preceding caption.

Jeff Davis County, Texas. June, early estival aspect (little current growth of warm-season grasses).FRES No. 38 (Plains Grassland Ecosystem). No appropriate units in Kuchler (1964, in Garricus, 1977) or Brown et al. (1998): both were much too general. Soil Conservation Service (Soil Survey, Jeff Davis County, Texas) Igneous Hill and Mountain range site in Mountain Grassland vegetation zone. Isolated unit of High Plains- Llano Estacado Ecoregion 25i within Chihuhuan Deserts- Low Mountains and Bajadas Ecoregion 24c (Griffith et al. 2004).

79. Plains-mesa grassland- Bluestem-grama mixed prarie in foothills of Davis Mountains of Trans-Pecos Basin and Range. This range vegetation was photographed prior to onset of summer rains leaving the previous season's herbage as a representation of mixed praire foothill grassland. Dominant species made a a "quaratete" of both cane and silver bluestem along with sideoats and bluegrama. Black, hairy, and chino grama were also common along with buffalograss, galleta, plains and bristlegrass. The major forb was silverleaf nightshade (Solanum elaeagnifolium). Presence of sacahuiste or, sometimes, beargrass (Nolina texana), large green clumps, has traditionally been associated with overgrazing and other human-induced disturbances. Powell (2000, p. 13 described grasslands with unnaturally high cover of sacahuiste as "modified". The current author could think of more descriptive terms for the change: degraded and deteriorated are two scientific terms that are appropriate for formal usage. Sacahuiste cover on this range-- aside from an aspect dominance appearance-- was interpreted as no more than light to moderate invasion.

Physiogonomy and structure of mixed prairie plains grassland was obvious in this mixture of mid- and shortgrass species.Cane bluestem specimens approached a height arbitrarily of tallgrass stature.

Brewster County, Texas. June, early estival period but still dormant to early growth stage for most grasses. FRES No. 38 (Plains Grassland Ecosystem). K-62 (Bluestem-Grama Prairie). SRM 714 (Grama-Bluestem), but variant of bluestem species. None of the series for Plains Grassland by Brown et al. (1998) could "mow the mustard" (too few series provided for this diverse grassland biotic community). Isolated unit of High Plains- Llano Estacado Ecoregion 25i within general Chihuhuan Deserts- Low Mountains and Bajadas Ecoregion 24c.

80. Texas sacahuiste or beargrass (Nolina texana)- This is one of the more widely distributed grass-resembling or liliaceous shrubs in the Great Plains and Trans-Pecos Basin and Range Regions. It is generlly unpalatable, but not enough. It is a poisonous range plant to sheep and goats under some conditions, namely when overstocking forces animals to eat and poison themselves or in years when flowers and fruit are in abundance. It is only flower parts and ripe fruit that cause toxicity: secondary or hepatogenic photosensitization. Hepatotoxicity is thought to be caused by accumulation of crystals from Nolina tissue in the bile duct. Cattle are not usually affected because they consume only leaves (Burrows and Tyrl, 2001, p. 16). Nolina species do provide valuable forage (browse) across some of the Western Range.

Students were referenced to the following references for discussions of sacahuiste poisoning: Kingsbury (1964, p. 56, 453-456), Sperry et al., (1964, p. 32-34), Burrows and Tyrl (2001, ps. 15-18), and Hart et al. (2003, p. 138).

Brown County, Texas. May.

82. Sand dune mixed prairie or, maybe, mixed prairie-shrub savanna- Vegetation is often deceiving. That fundamental principle was examplified by this mixed prairie on dune land. Sparcity of vegetation cover and low density of plants would suggest to the greenhorn a desert, but in reality structure and composition of this range plant community consisted of tall-, mid-, and shortgrass species producing a classic mixed prairie (in spite of sparcity of plants and plant cover). Major grass species included little bluestem, sand bluestem, sand dropseed, sand paspalum (Paspalum stramineum= setaceum var. stramineum)and perennial threeawn (Aristida purpurea complex). There were a few plants of showy fingergrass (Chloris virgata) but presence of this annual species was of little diagnostic utility. Likewise the presence of a few specimens of common sandbur (Cenchrus incertus) suggested nothing beyond the ever-present annoyance of this weed. Under virgin conditions it was likely that big sandreed (Calamovilfa gigantea) and giant dropseed (Sporobolus giganteus) were present as key indicator species. Neither of these climax species was not found at this location.

The deception (and complication) of this dune land vegetation extended to the shrubs that were present. Mixed and shortgrass prairie grasslands and sand shinnery oak (Quercus havardii) shrubland develop in a mosaic of climax vegetation throughout this region. Presence of numerous shrubs that are climax in the "shinnery sands", the sand shinnery range type (ecosystem), were also present. These shrubs-- in certain proportions-- are thus climax components of the vegetation shown in above photographs. This range plant community was actually a transition zone (= ecotone) between grassland and shrubland vegetation such that it developed into a grass-shrub savanna. These shrubs included sand shinnery oak, the scrub growth (= coppice) form of honey mesquite, and (infrequently) sand sagebrush.

An estimate of annual biomass productivity (so as NOT to be confused by accumulated plant tissue that included necromas accumulated in woody species), species diversity, and plant cover of each growing season convinced this photographer-student that this range vegetation was clearly grassland and not shrubland. This conclusion was further bolstered by the almost-always assumption that that there had been some range deterioration (= degree of departure from climax) if, by nothing else the ubiauituous increase in mesquite since arrival of whiteman. Nonetheless, it was also obvious (again, at least to the rangeman taking these photographs) that this range vegetation was a mixed prairie-shrub savanna. The shrubs are a part of this climax.

Forbs included yellow whollywhite or yellow old plainsman (shown above in this chapter) and western sensitive-briar (Schrankia occidentalis) which was introduced in the succeeding photograph.

Local topography or land form on which this range cover type developed was hummocky (circular sandy hummocks) rather than the tall dune form. The first photographs was taken from the bottom of an interdunal basin in foreground with slopes and the rim or crest (top) of the hummock in background. The second photograph was taken from the intra-dune (intra-hummock) mid-slope (foreground) across the basin (which is bottom of this inter-dunal area) to the crest (behind which is another interdunal hummock with its basin, sloping sides, and crest or rim).

Monahans Sandhills State Park, Ward County, Texas. June. FRES No. 31 Shinnery Shrubland Ecosystem & No. 38 (Plains Grassland Ecosystem) transition zone. No truly descriptive Kuchler unit. SRM 708 (Bluestem-Dropseed), and a textbook of the sparse form or expression of this rangeland cover type.There was no appropriate series under the Brown et al. (1998) Plains Grassland biotic community: inadequate Series units for this large and diverse zonal or regional community of plains grassland climax. High Plains- Shinnery Sands Ecoregion 25j (Griffith et al., 2004).

84. Great Plains-Great Basin transition mixed prairie grassland- Landscape-scale photograph of what Brown (1994, p.119) described in a photo caption as a "Plains grassland-Great Basin grassland transition", "... a mixture of both Plains species (Boutelous gracilis) and Great Basin species (Hilaria jamesii, Oryzopsis hymenoides)" and "... shrubs are mostly fourwing saltbush (Atriplex canescens)". The range vegetation shown in this slide was an example of plains and mesa grassland described by Dick-Peddie (1993, p. 119) and quoted in the last paragraph of the preceding slide caption. This climax vegetation was a consociation of New Mexico feathergrass (= New Mexico needlegrass) with blue grama, galleta, and Indian ricegrass approximately "equally divided" and functioning as associate species. Sand dropseed was present at more than "trace amounts", but it was not a major component. Greasewood (Sarcaobatus vermiculatus) and Bigelow sagebrush (Artemesia bigelovii) were the two most common shrubs with greasewood better represented. Fourwing saltbush was present (rarely) and perhaps as a relict species. None of these woody species accounted for more than trace proportions. Broom snakeweed was present but even more rare. Forbs were represented (barely) by Russian thistle and Thurber pepper-weed (Lepidium thurberi).

Relative utilization or degree of use of grass was light even under current conditions of exceptional drought. It was noted that sexual reproduction of feathergrass was remarkable for such short-moisture conditions. Winter precipitation had "saved the day" for this species.

Grand Canyon section of the Colorado Plateau physiographic province.

Coconino County, Arizona. Estival aspect during worst drought (exceptional rating) in Arizona history, June. FRES No. 38 (Plains Grassland Ecosystem). K-47 (Gramagrass-Gallata Steppe).SRM 716 (Grama-Feathergrass).

85. Vegetation of Great Plains-Great Basin transition mixed prairie- This photograph detailed at community scale the climax vegetation of the New Mexico feathergrass consociation of plains and mesa grassland, a variant of the regional gramagrass-gallata (Bouteloua-Hilaria) climax steppe. Dominance by a cespitose midgrass (a species of intermediate height between tallgrass and shortgrass) produced a physiognomy typical of mixed prairie, but absence of a tallgrass species resulted in absence of one herbaceous layer that was present in some of the other range cover types of mixed prairie.

Cover and dentisty of woody species were so limited that a shrub layer was also absent. This climax community was not a savanna-like shrub steppe, but rare presence of fourwing saltbush was of uncertain interpretation. Brown (1994, p.104) specified presence of fourwing saltbush in a similar transition grassland community located close to the one shown here, but neither Dick-Peddie (1993, p. 104-106) nor the the SRM description of this rangeland cover type, SRM 716 (Grama-Feathergrass), (Shiflet, 1994, ps. 94-95) specifically reported fourwing saltbush for this vegetation. The SRM description (Shiflet, 1994) was limited to eastern New Mexico which was essentially in the High Plains province rather than the Colorado Plateau as shown here. Likewise, none of these descriptions mentioned greasewood which was certainly the most common (least uncommon) shrub and one known to occur here.

Perhaps browsing by livestock and/or wildlife had reduced fourwing saltbush. It was conceivable also that grazing had shifted dominance from the regionally dominant blue grama to the co-dominat New Mexico feathergrass. Existing "on-the-ground" evidence argued against both of these outcomes. Species composition of vegetation in the wide right-of-way of Interstate 40 was not apparently different from that inside the range allotment except that the rarely encountered fourwing saltbush plants were larger in the right-of-way. Right-of-way vegetation had been protected from grazing and routine mowing for several decades and this could explain larger size of fourwing saltbush specimens. Otherwise the only difference between livestock presence and absence appeared to be in degree of use (and not species composition of plant community). Present (and immediately past) grazing management of the range appeared to be ideal, an example of outstanding stewardship.

Fourwing saltbush was present (far right to center midground) on New Mexico feathergrass-dominated range protected from livestock grazing and not subjected to highway mowing (shredding).

Coconino County, Arizona. Early estival aspect (conditions of exceptional drought), June. FRES No. 38 (Plains Grassland Ecosystem). K-47 (Gramagrass-Galleta Steppe). SRM 716 (Grama-Feathergrass).

86. Patch dynamics in vegetation of Great Plains-Great Basin transition mixed prairie range- These paired photographs showed details of undisturbed vegetation (first or upper slide) and disturbed vegetation (second or lower slide) of a New Mexico feathergrass-dominated (feathergrass consociation) bunchgrass steppe on the Grand Canyon section of the Colorado Plateau province. The localized "patch" in the lower photograph had Russian thistle (round-shape tumbleweed in lower left), greasewood (largest plant; center background), Bigelow sagebrush (to immediate right of greasewood), fourwing saltbush (immediately to right and also behind Bigelow sagebrush), broom snakeweed (right background), and Indian ricegrass (right-center foreground) as well as New Mexico feathergrass in contrast to the nearly single-species stand of New Mexico feathergrasss in the undistrubed patch shown in the upper photograph. This was an example of patch dynamics on a very local scale (microsite-size). Both patches were on highway right-of way not subjected to mowing.

Coconino County, Arizona. Early estival aspect (in exceptional drought), June. FRES No. 38 (Plains Grassland Ecosystem). K-47 (Gramagrass-Galleta Steppe). SRM 716 (Grama-Feathergrass).

90. Bigelow sagebrush (Artemesia bigelovii)- Both this species and big sagebrush (A. tridentata) grow in the Great Plains-Great Basin transition mixed prairie steppe on the Colorado Plateau. Bigelow sagebrush can be readily distinguished by presence of numerous stems in contrast to the usual single trunk of big sagebrush.

This specimen was growing on the climax New Mexico feathergrass-dominated range and exclosed area shown above. Coconino County, Arizona. June.

91. Galleta-blue grama plains and mesa grassland in drought- Appearance of High Plains (Llano Estacado) mixed prairie in prolonged, severe drought and under current overuse. Galleta was the obvious dominant species with blue grama, buffalograss, western wheatgrass, and sand dropseed all microsite associate species and in that relative mean (overall range community) order of abundance. This range had absolutely no mesquite, but the native plains pricklypear (Opuntia polyacantha)-- seen as small isolated patches in foreground-- had begun to appear at density and cover of an invader (greater amounts than in climax vegetation). It must be borne in mind, however, that overuse of grass had exposed pricklypear prominently. Nonetheless, there was virtually no doubt but what this range was probably being mismanaged-- to some detriment of both range and cattle. Excessive degree of use (overuse= removal by grazing animals of excessive portions of current season's leaves and stems that if conitinued will lead to overgrazing) was indeniable.

The most immediate incontrovertible evidence of current overuse was grazing of young, growing plants of broadleaf milkweed (Asclepias latifolia) by cattle. A. latifolia is one of the more toxic plants on High Plains ranges (perhaps because there are not as many poisonous plant species in this region as in some of the more botanically diverse adjoining ones like the Trans Pecos Basin and Range and Edwards Plateau). Livestock poisoning by broadleaf milkweed is enough of a problem that it was routinely covered in standard textbooks and Agricultural Experiment Station-Extension publications (eg. Sperry et al., undated). In the example shown here it was human management of range and cattle that resulted in milkweed consumption. There was no evidence of toxicity to cattle: apparently quantities eaten were below toxic levels (at time of photograph). If current overstocking does not result in overgrazing (range retrogression due to prolongued overuse) with corresponding damage to basic range resources like soil and watershed features and/or economic losses in livestock (in excess of that from emergency feeding), such periods of overuse cannot automatically be labeled as mismanagement. Cows and calves grazing this range remained in thrifty condition and as the grass species were in semi-dormancy the range was not being severely abused. The situation was that there were indications that current grazing management was allowing invasion by plains pricklypear. More frequent movement of cattle to different pastures or even culling of lower-producing cows might well be more economical in the long run.

Examples of broadleaf milkweed were presented below in this Mixed Prairie portion. The large Brangus cow beside the cholla indicated size of some of these cactus plants.

Guadalupe County, New Mexico. Early estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-58 (Gramagrass-Buffalograss). SRM 705 (Grama-Galleta). Grama "Short-Grass" Series of Brown et al (1998). Southwestern Tablelands- Conchas/Pecos Plains Ecoregion, 26n (Omernik and Griffith, 2006).

92. Sward of plains and mesa mixed prairie in drought and without cattle grazing- Details of galleta-blue grama-buffalograss-western wheatgrass-sand dropseed (all are visible) community shown in the preceding photograph except that grass shown in this photograph was not grazed. Vegetation seen here was immediately adjacent to but outside the fence that enclosed the currently overused range of plains and mesa mixed prairie. Difference in degree of use was obvious, but there was little difference in species composition except for absence of broadleaf milkweed and less cover of plains pricklypear. Grazing by cattle had apparently contributed to an increased number of plant species and a somewhat different plant "mixture" (ie. cattle grazing apparently increased biological diversity). Is this sort of increased biodiversity "good" or "bad"?

Western wheatgrass photographed here was in anthesis. Western wheatgrass inside the pasture shown in the preceding slide was grazed to a stubble height of less than two inches and there were no flowering shoots. In other words, even in severe, early season drought cool-season grasses were in the process of producing seed-- where they were not "grazed into the ground".

Degree of use is determined largely by the stocking rate. Proper degree of use (proper stocking rate) is the first and most important of the Four Cardinal Principles of Range Management.

Guadalupe County, New Mexico. Early estival aspect, June. FRES No. 38 (Plains Grassland Ecosystem). K-58 (Gramagrass-Buffalograss). SRM 705 (Grama-Galleta). Grama "Short-Grass" Series of Brown et al (1998). Southwestern Tablelands- Conchas/Pecos Plains Ecoregion, 26n (Omernik and Griffith, 2006).

93. Relict plains-mesa mixed prairie (shrub steppe form)- Although this semiarid grassland in the Datil section of the Colorado Plateau was enduring a severe to exceptional drought and in semi-dormancy it was the potential natural vegetation. These two photographs showed the species composition and physiogonomy of a climax mixed prairie grassland with a shrub component that appeared almost as a shrub-grassland savanna. The climax dominant shrub was fourwing saltbush. There was an occasional broom snakeweed (an all-too-common invader on adjacent range), but the vegetation here was in "mint condition". On the extremely sandy soil of this range site Indian ricegrass was the clear dominant with sand dropseed, plains lovegrass, blue grama, and sideoats grama all abundant species and growing as mixed localized "mini-communities". Sand dropseed dominated some microsites. Blue grama, the dominant species of this general regional (monoclimax or ecoregion dominant) was never a local dominant on this sandy range. Galleta was not present (or if missed, it was but a trace).

Cibola County, New Mexico. Early vernal aspect (extreme to exceptional drought), June. FRES No. 38 (Plains Grassland Ecosystem). K-47 (Gramagrass-Galleta Steppe). Variant of SRM 502 (Grama-Galleta); SRM 705 (Blue Grama-Galleta) occurs to the east of the 502 rangeland cover type but resembles it rather closely.

Dick-Peddie (1993, p. 104) described this and the mixed prairie example in the succeeding slide, Great Plains grassland-Great Basin grassland transition, as part of the plains and mesa grassland in which blue grama was a common denominator but often co-dominant with galleta on mesas in the northern half of New Mexico. He specified: "On fine-textured soils in the north and northwest, Indian ricegrass (Oryzoides hymenoides) may share dominance with blue grama, or communities can be found with New Mexico feathergrass (Stipa neomexicana) and needle-and-thread (S. comata) sharing dominance with blue grama" (Dick-Peddie, 1993, p. 119). Arizona/New Mexico Plateau- Semiarid Tablelands Ecoregion, 22j (Omernik and Griffith, 2006).

Phenological/species compositional note: photographs of rangeland cover types Wheatgrass-Grama-Needlegrass (SRM 608) & Wheatgrass-Needlegrass (SRM 607) taken in June 2008 gave an atypical representation of  these types. A late spring (abnormally cold and wet) was a boon for needlegrass species and “hard scramble” growing conditions for wheatgrass species. Although slides were taken in early summer, phonological stages of most species— especially western wheatgrass—were those typically taking place much earlier in the growing season. Aspects, especially aspect dominance, structure, and relative composition of these mixed prairie communities were generally those of vernal societies at a time in growing season when estival aspects and societies normally would have predominated. Again, western wheatgrass in particular was underrepresented from average composition (based on relative cover), structure, and overall physiogonomy. Also, in early summer blue grama was still in early vegetative stages of phenology so as to be vastly underrepresented from the standpoint of cover dominance. Simply put, photographs were of the vernal rather than estival societies of these types.

These clarifying notes made, it should also be stressed that these photographs did display clearly the dominance of needle-and-thread (Stipa comata) which has traditionally been regarded as the overall first defining co-dominant of the mixed prairie (Stipa-Sporobolus) association (Dodd in Gould and Shaw, 1968, 1983, ps. 349-351) which traced back to the seminal knowledge of Clements (1920, ps. 122, 135-138) and Weaver and Clements (1938, ps. 523-524). Incidentially, more recent interpretations appeared to have placed needle-and-thread "second in command" to blue grama and/or western wheatgrass as can be seen in titles of potential natural vegetation by Kuchler (1964, 1966) and the Society for Range Management Shiflet (1994) shown below. The photographs presented below--even allowing for aspect dominance and an estival aspect--suggested that initial interpretations by Clements (1920) and Weaver and Clements (1938) and subsequently by Dodd (in Gould and Shaw, 1968, 1983) were closer to the mark.

94. Transition zone mixed prairie- Mixed prairie dominated by needle-and-thread, blue grama, and western wheatgrass in lower foothills of the Southern Rocky Mountains in a patchwork pattern of range vegetation with true mountain mahogany (Cercocarpus montanus) shrubland. This scrub range type was treated in the Mountain Scrub chapter under Shrublands. To reduce confusion the mountain mahogany scrubland was not described here.

Additional important--at least locally so--grasses included Junegrass (Koeleria cristata= K. pyramidata), slender wheatgrass (Agropyron trachycaulum), bluebunch wheatgrass (A. spicatum), Sandberg's bluegrass (Poa secunda), big bluegrass (P. ampla), Canby's bluegrass (P. canby), plains bluegrass (P. arida), squirreltail (Sitanion hystrix), some Indian ricegrrass (Orysopsis hymenoides), occasional plants of little bluestem (Andropogon scoparius=Schizachyrium scoparium), local stands of cheatgrass (Bromus tectorum), and scattered plants of the naturalized, Eurasian crested wheatgrass (Agropyron cristatum).

Forbs were limited but the most common one at this season was whiskbroom parsley (Harbouria trachypleura). Shrubs, other than true mountain mahogany at grassland-shrubland contact, were absent except for an occasional plant of fringed sagewort (Artemisia frigida).

Laramie County, Wyoming. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Southern Rockies- Mid-Elevation Forests and Shrublands Ecosystem, 21c (Chapman et al., 2003).

95. Sward of foothill mixed prairie- "Photo-quadrant" of mixed prairie in an area of transition from western edge of Great Plains to foothills of the Southern Rockies. Needle-and-thread was the overwhelming dominant with western wheatgrass (which was underrepreented in this particular spring-summer period) and blue grama (early in the year for full vegetative expression of it) the associate species. Other grasses included Junegrass, slender wheatgrass, bluebunch wheatgrass, Indian ricegrass, Sandberg's bluegrass, big bluegrass, Canby's bluegrass, plains bluegrass, little bluestem, and, as always, cheatgrass.

Principal forb at this season was whiskbroom parsley. Shrubs were absent except for infrequent fringed sagewort (when this is interpreted as a shrub). This was grassland in purest sense of the term, and it was grassland in Excellent range condition class.

. Laramie County, Wyoming. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Southern Rockies- Mid-Elevation Forests and Shrublands Ecosystem, 21c (Chapman et al., 2003).

This next section of mixed prairie range presented four ranges of the needle-and-thread--western wheatgrass--blue grama grazing type (SRM 608) in Excellent, Good, Fair, and Poor range condition class. These four pastures were photographed on the same day (2 June) within about three hours and 25 miles of each other (three pastures were in Niobrara County, Wyoming and one range was in Sioux County, Nebraska). Photographs were taken with a wide-angle (28mm) lense so there were several range sites in each landscape-scale photograph, but for comparative purposes photographs featured the same or similar range sites in their foregrounds which was flatter rangeland on benches and not tops or sides of hills. None of the rangeland presented in these slides was near enough to a sacrifice area to bias views of range vegetation.

Key feature of this range type- The "mixed" characteristic of this form, this rangeland cover type, of mixed prairie was through dominance by three midgrass species. There was not a tallgrass component--at least not as a dominant species--in this type-level range plant community. This was in contrast to the Wheatgrass-Bluestem-Needlegrass rangeland cover type (SRM 606) which had sand bluestem as a dominant tallgrass species. The needle-and-thread--western wheatgrass--blue grama type did,however, include both dominant cool-season and warm-season species. This contrasted with the Wheatgrass-Needlegrass rangeland cover type (SRM 607 ) which lacked a warm-season dominant.

96. Mixed prairie in all its glory; first of a comparison- Central Great Plains grassland dominated by needle-and-thread, blue grama, and western wheatgrass with Indian riecgrass and threadleaf sedge (Carex filifolia) associate species. Forbs included crested tongue penstemon or crested beardtongue (Penstemon eriantherus), silvery lupine (Lupinus argenteus), scarlet globemallow (Sphaeralocea coccinea), and a speciimen of an unknown Astragalus species.

This range plant community did not have a particularily rich flora, but it was in mint condition. This was textbook climax mixed prairie of the central grassland formation, grassland like it was when God had it by Himself. A wll-earned stewardship salute to this private landowner.

Note: this range was being grazed at a light degree of use. It was photogrphed at peak standing crop for cool-season perennial grasses (ie. vernal society of the range plant community) which automatically overrepresented needle-and-thread, western wheatgrass, indian ricegrass, and threadleaf sedge relative to warm-season species like the third dominant blue grama. Viewers should not confuse views or perceptions of vegetation resulting from utilization (degree of use) with those due to species composition. This must also be borne in mind when viewing and comparing ranges shown below.

Niobrara County, Wyoming. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2003).

97. Sward of western mixed prairie in mint condition- Two 'photo-plots" of the sward of the Excellent condition class range of western mixed prairie presented in the immediately preceding pair of photographs. In the first of these "plots" needle-and-thread and western wheatgrass, which along with blue grama, were the overall dominants, made up the cover in left background while threadleaf sedge dominated most of the rest of this sample of range vegetation. In the second "plot" threadleaf sedge was the local dominant with western wheatgrass and needle-and-thread in control of microsites in the background. Main forb was fringed sagewort or fringed sagebrush. There were a few individuals of the Eurasian weed, goat'sbeard (Tragoypogon dubius).

Niobrara County, Wyoming. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2003)

98. Western mixed prairie; second of a comparison- Another range in the western Central Great Plains comprised of needle-and-thread, western wheatgrass, and blue grama. Like the preceding range used as an example of this cover type (two sets of paired photographs just shown) needle-and-thread was dominant and conspicuous. (Recall from introduction to this set of slides that it had been a near-perfect for Stipa comata.) Unlike the first example that was Excellent condition class range the one shown here and in the next photograph, was in Good condition class. This range had been graazed with a greater degree of use (low end of moderate) than the range presented immediately above, but the meaningful difference between between these two ranges was in species composition not utilization.

The range shown here and in the follow-up view of the sward had much less western wheatgrass and blue grama and instead had Sandberg's bluegrass as the associate species. This pasture also had considerably greater cover of cheatgrass. There was also slightly more fringed sagewort on the range shown here. Other species included plains bluegrass, threadleaf sedge, and even Indian ricegrass, but cover (basal and foliar) of these--even allowing for greater degree of use--was substantially less than on the Excellent condition range.

Range sites were similar, at least enough for comparison. No, the difference in species composition had been previous--not current season--grazing management.

Niobrara County, Wyoming. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2003)

99. Sward of mixed prairie in Good condition- A "photo-plot" of range vegetation on the Good condition class range introduced in the immediately preceding slide. Needle-and-thread was still dominant and there was still some cover of decreaser forage speciees like Indian ricegrass and threadleaf sedge. This was substantially less than on the Exeellent condition class range presented and described above. There was also considerably greater incidence and cover of cheatgrass at local scale (although little was shown here). Incidence of miscellaneous forbs (mostly commposites) was also greater on this Good than on the Excellent condition range.

Degree of use of the range overall was in the moderate category.

Niobrara County, Wyoming. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2003)

100. Western mixed prairie; third of a comparison- A third range of the needle-and-thread-western wheatgrass-blue grama type of mixed prairie in the Central Great Plains. This one was under high fence for the explicit purpose of grazing North American buffalo (Bison bison). Unfortunately for this former reigning ruminant of the central grasslands of the plains this range was in Fair range condition class. Needle-and-thread, generally the defining dominant of mixed prairie in this region, was still the dominant perennial grass. At least this was the situation on this range at end of the growing season for cool-season species (period of the vernal society) and prior to main portion of growth for blue grama, the regional warm-season dominant.

Even though needle-and-thread was the dominant native grass, the dominant range plant on this range (the one with greatest cover, density, and biomass) was the Mediterranean, weedy annual cheatgrass. Cheatgrass was conspicuous as the reddish or off-color purple coloration in the foreground. Naturalized and self-seeded crested wheatgrass was also present as scattered individuals on the degraded range featured in the foreground. On hills in the background there was much less cheatgrass and, in fact, that range vegetation was Good to Excellent condition range like that shown for the "mint" condition range used at start of this comparison. Note, however, that range vegetation on hillsides and hilltops was not compared in any of these photographs. Rather it was vegetation on benches and on rangeland with less relief that was used for comparative pruposes of all ranges. Range vegetation that was presented for purposes of comparison as to species composition was on similar slopes, aspects, and as close to comparable range sites as possible among available pastures.

Likewise, the pasture shown here had degree of use (light) similar to that of the first pasture, the "mint" condition range, and lighter defoliation than that of the previous range that was in Good condition class and had moderate degree of use at time of photograph. It was obvious that past grazing had been considerably greater (heavier degree of use or utilization) on the flatter rangeland (foreground) than on hillsides of the range featured here. This may have been attributable to grazing by cattle in the recent past with buffalo being a recent reintroduction. Evidence of this possibility was the "brand new" high game fence that enclosed this range. It would be an almost foregone conclusion or assumption that beef cattle had been the major species of range animal before bufffalo had been restocked on their former range by the present landowner who quite obviously "had more money than he knew what to do with".

Regardless, this was an example of needle-and-thread dominated mixed prairie in Fair range condition class that can be compared to those of the same range type (and similar range site) in Excellent and Good condition class (above) and Poor condition class (coming up next).

Niobrara County, Wyoming. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2003).

101. Western mixed prairie; fourth of a comparison- A fourth range of the needle-and-thread-western wheatgrass-blue grama type of mixed prairie in the western Central Great Plains. Can there be any doubt that this pathetic degraded example was in Poor condition class? The green (and gnawed down) spots were remains of needle-and-thread and western wheatgrass. The silvery bunches were fringed sagewort. Reddish brown patches were local stands of cheatgrass. The one taller, green bunch of grass was crested wheatgrass which, incidentially, attested to the low palatability of this introduced and naturalized range grass compared to palatability of native grasses like needle-and-thread and western wheatgrass. There was also Sandberg's and plains bluegrasses along with the native annual, sixweek's fescue (Festuca octoflora).

Degree of use on palatable decreaser species was relatively high or close under heavy grazing. Obviously there was little grazing use made of fringed sagewort and invaders like cheatgrass. This Poor (and sadly unfortunate) range had a long history of overuse (obviously stretching over a number of years) so that the misuse had gone to the state of overgrazing. This range was in such a state of degradation (retrogression of range vegetation on this sere) that it almost required a "crime scene uinvestigator" to identify "species of the corpse". Compare the stewardship of this landowner (or renter) and, maybe, previous graziers to that of the good and faaithful stewards wisely using the Excellent and Good condition class ranges presented previously.

Sioux County, Nebraska. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Western High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2001).

102. 'bout droughted-out but a mixture sho' 'nough- A relatively grass species-rich "sample" in two 'photo-plots" of climax mixed prairie in the Central Great Plains. Needle-and-thread, blue grama, and western wheatgrass were about equally dominant on this ungrazed (perhaps deferred) range. Sideoats grama, buffalograss, sand dropseed, red threeawn, hairy grama, and cheatgrass were other species that were varied from infrequent (eg. hairy grama) to abundant at local scale (eg. sand dropseed, buffalograss, sideoats grama) Cheatgrass was limited to local disturbed spots. Forbs were extremely limited with incidental composites comprising most of these.. The most common (though infrequent) shrub species were plains pricklypear and soapweed yucca.

The plants on this range were largely dormant in early summer during second year of a moderately severe drought. This combined with recent absence of grazing resulted in these photogenic shots of the potential natural vegetation on a western expanse of Central High Plains.

Pawnee National Grassland, Weld County, Colorado. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it High Plains- Moderate Relief Plains Ecoregion, 25c (Chapman et al., 2006).

103. Grazing disclimax of mixed prairie- A mixed prairie dominated by needle-and-thread with Indian ricegrass as associate converted into a buffalograss-blue grama short grass (co-dominants) disturbance climax by longtern overgrazing by cattle. The associate grass species was sixweeks fescue, a native annual festucoid species. The conspicuous yellow composite was stiff greenthread (Thelosperma filifolium var intermedium) and the white infloresences were on pale or white evening-primrose (Oenothera albicaluis) an annual.member of Onagraceae. (Both of these forbs were shown below with other species from this area.)

Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 38 (Plains Grassland Ecosystem). Mixture of K-57 (Grama-Needlegrass-Wheatgrass) and K-58 (Grama-Buffalograss). SRM 608 (Wheatgrass-Grama-Needlegrass). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13,, High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

104. Disturbed carpet- Sward of buffalograss-blue grama disturbance climax that replaced a needle-and-thread-dominated mixed prairie tht was the potential natural plant community (climatic climax). View of sward on the shortgrass disclimax introduced immediately above. In addition to the co-dominants other major species included sixweeks fescue, the associate grass, and stiff green thread and pale evening-primrose, the two most abundant forbs on this range. There were a few closely cropped plants of neeedle-and-thread, but the author could not find any Indian ricegrass (none of sufficient size to be identifiable anyway).

Note: range vegetation presented in this and the preceding photograp were typical or representative samples of the overgrazed range. They were not in a sacrifice area. More on this important point in the immediately following caption.

Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 38 (Plains Grassland Ecosystem). Mixture of K-57 (Grama-Needlegrass-Wheatgrass) and K-58 (Grama-Buffalograss). SRM 608 (Wheatgrass-Grama-Needlegrass). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

105. What was before (or The fence made the difference)- Relict needle-and-thread--dominated mixed prairie (Indian ricegrass was associate species) on the other side of the fence from the buffalograss-blue grama disturbance climax shown in the two immediately preceding slides. Buffalograss, blue grama, and sixweeks fescue were also common and important members of this protected strip of grassland, but the fence separated climax bunchgrass mixed prairie from disclimax shortgrass. Overgrazing (longterm overuse), by cattle in this case, was responsible for this range type conversion.

The two most common forbs in the exclosure were stiff greenthread and pale evening-primrose the same as in the overgrazed pasture. Pale evening-primrose appeared to be about as abundant on one side of the fence as the other, but stiff greenthread was clearly much denser and of greater cover on the overgrazed range.

Specification: there was a ranch road that ran alongside the fence on the overgrazed range (visible in both of the photographs described in this caption). The immediately preceding photographs of this shortgrass disclimax were not taken either in or adjacent to the ranch road, but rather out in representative portions of the overgrazed range. Range vegetation presented in the two above slides was not in the sacrifice area of the ranch road.

Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 38 (Plains Grassland Ecosystem). Mixture of K-57 (Grama-Needlegrass-Wheatgrass) and K-58 (Grama-Buffalograss). SRM 608 (Wheatgrass-Grama-Needlegrass). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

106. Overgrazing by the natives- A town of black-tailed prairie dog (Cynomys ludovicianus) on severely degraded High Plains range on which the climax (potential natural vegetation) was a needle-and-thread--dominated mixed prairie with blue grama, buffalograss, and Indian ricegrass as associates. This was the same range site, Loamy Plains, as that of the cattle-induced shortgrass disclimax and the undisturbed needle-and-thread mixed prairie described immediately above. Along this railroad right-of-way black-tailed prairie dogs had established their town resulting in much bare soil and plant cover primarily of plains pricklypear and with stiff greenthread, pale evening-primrose and/or scarlet globemallow supplying most of the herbaceous cover with relative proportions varying at microscale. All remaining blue grama (of which there was little) had been closely clipped so that the about the only remaining grass cover was that of buffalograss. There was not even much cover of cheatgrass which, along with buffalograss, was relatively abundant immediately below track bed of the railroad.

That needle-and-thread was the potential natural dominant (as on the exclosure--outside of the fence--shown above) was clearly shown by two plants of needle-and-thread in the middle of pricklypear patches where, of course, prairie dogs did not venture.

How "natural"--if natural at all--was a "dog town" on railroad tract exclosures? The answer was unknown to this author, but he hastened to point out that range plant communities along railroad rights-of-way have long been regarded as relict vegetation. Railroad corridors have served as relict areas or reference vegetation for decades. Railroad rights-of-way are about the only sources of native prairie left in much of the Corn-Soybean Belt. Abandoned tracks are now used as hiking trails, bridle paths, and "natural parks".

Anyway, prairie dogs had degraded this mixed prairie vegetation to a much lower seral stage (including.contributing to brush [pricklypear] invasion).

Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 38 (Plains Grassland Ecosystem). Mixture of K-57 (Grama-Needlegrass-Wheatgrass) and K-58 (Grama-Buffalograss). SRM 608 (Wheatgrass-Grama-Needlegrass). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

107. Mixed prairie mosaic- Two acrosss-the-land vistas of climax mixed prairie in the Central High Plains. This grassland had as its apparent potential natural vegetation a vegetational mosaic "put together" as intermixed intermediate-size areas of 1) blue grama-buffalograss shortgrass; 2) needle-and-thread-dominated midgrass; 3) western wheatgrass consociations; and 4) scattered plants of sand dropseed, red threeawn, needleleaf [caric] sedge (Carex duriuscula= C. eleocharis= C. stenophylla ssp. eleocharis), fringed sagebrush, scarlet globemallow, pale evening-primrose, stiff greenthread, wild alfalfa or slender scurfpea (Psoralea tenuifolia), and plains pricklypear, this latter being the sole shrub component of this vegetation. A tallgrass element was lacking from this mixed prairie this grassland being a midgrass-shortgrass prairie which--as was shown above and below--on certain range sites was readily degraded into a grazing shortgrass disturbance climax.

The first of thee two photographs featured an area of buffalograss-blue grama shortgrass turf with considerable cover of plains pricklyper. the second photograph local "spots" of shortgrass and wesstern wheatgrass colonies in foreground with stands of needle-and-thread, sand dropseed, and red threeawn in midground. Most common (and conspicuous at this season) forb was stiff greenthread. Both buffalograss and needle-and-thread were at peak anthesis while western wheatgrass spikes had just emerged from their boots. Blue grama was "a long-way off" from blooming and, in fact, had not in the main elongeted its shoots beyond mid-height of adult stature. More precisely, blue grama was not at adult stage in this vernal society. Thus blue grama was under-represented in the vernal aspect and in overall appearance. Conversely, needle-and-thread, a cool-season midgrass, was over-represented in these photographs; however, it would have under-represented while blue grama would have over-represented a month to six weeks later at peak of warm-growing season and estival aspect. Such is the nature of range plant communities that are "natural mixtures" of cool-season and warm-season species each group of which has species that are dominants and associates in their own season.

Time (seaonal progression) of phenological development was a major component or characteristic of mixed prairie vegetation in all of these photographs.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 38 (Plains Grassland Ecosystem). Mixture of K-57 (Grama-Needlegrass-Wheatgrass) and K-58 (Grama-Buffalograss). SRM 608 (Wheatgrass-Grama-Needlegrass) and SRM 611 (Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

108. Integration of midgrasses and shortgrasses- "Photoquadrant" of range vegetation on a midgrass-shortgrass mixed prairie in Central Great (High) Plains. Species ranged from the midgrasses, western wheatgrass and needle-and-thread down to shortgrasses (mostly buffalograss and blue grama) plus needleleaf caric sedge and such forbs as fringed sage, stiff greenthread, pale evening-primrose along with a shrub component in plains pricklypear.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

109. Botanical quilt (or What makes a mixed praire) - More of the mixed prairie patchwork consisting of both midgrass and shortgrass species. In these two "phototransects" the dominant midgrass (and dominant vernal) species was needle-and-thread with sand dropseed the local associate midgrass. Both of these species were conspicuous in both photographs. The dominant shortgrass at this vernal stage of the annual cycle (ie. vernal aspect) and in this vernal society was buffalograss which was at peak anthesis. Blue grama was the local associate shortgrass though at other local habitats (microsite) blue grama was co-dominant. Blue grama would be predominant over buffalograss in the In the estival aspect and society by which time blue grama whould have attained adult growth of shoots. Conspicuous forbs were stiff greenthread (first photograph) and scarlet globemallow (second photograph). There were scattered plants of fringed sage and wild alfalfa or slender scurfpea. Plains pricklypear was so sparse as to be undectable in these photographs.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

110. Three cuurtain calls for the botanical cast- Three "photoquadrants" showing the range plant community with representative species of a midgrass-shortgrass mixed prairie in the Central Great (High) Plains at peak standing crop of the vernal society. The first of these three photographs showed the "fenceline-like" edge between a local midgrass community (dominated by needle-and-thread in this example) and a local shortgrass community (co-dominated by buffalograss and blue grama in this example). These local communiites could be regarded as herbaceous stands.

The second photograph was of a more composite community where shortgrass and midgrass stands overlapped as a local ecotone (transition zone at local scale). Range plant species in this second "photoquadrant" included blue grama, buffalograss, sand dropseed, red threeawn, western wheatgrass, needleleaf sedge, fringed sage(brush), scarlet globemallow, and plains pricklypear.

The third "photoquadrant" was still yet another local community which in this instance was a midgrass stand of needle-and-thread (primarily) and sand dropseed (secondarily) with plains pricklypear as a ground-level shrub. The pricklypear (along with pale evening-primrose) was in flower.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

111. Co-dominant shortgrasses- Ground-level views of the two dominant shortgrass species, blue grama and buffalograss, on a Loamy Plains range site in the Central Great (High) Plains in late vernal aspect and vernal society. Blue grama was on the left in the first slide and on the right in the second slide and vice versa for buffalograss.

Buffalograss was at its maximum vegetative and floral stages of phenological development (full-growth stage of annual shoot elongation [unless very fortunate amble moisture caused later growth] and peak anthesis) whereas the later-maturing blue grama had made a much lower proportion of its annual shoot growth/development at this point in the current growing season. On the Central Plains Experimental Range Dickinson and Dodd (1976) studied phenological development of major plant species and reported that time of flowring was frequently inconsistent with regards to warm- vs. cool-season species. For example, the warm-season buffalograss bloomed at roughly the same time as the cool-season western wheatgrass. Likewise, time of anthesis in cool-season species, needle-and-thread and bottlebrush squirreltail, could be closer to that of buffalograss than buffalograss was to the other warm-season dominant shortgrass, blue grama (Dickinson and Dodd, 1976, table 2). Unlike most other Bouteloua species blue grama is a long-day plant with regard to flowering (Olmsted, 1943). On the range shown here blue grama more commonly bloomed in late June to July (Dickinson and Dodd, 1976, table 2).

The major differences between these two erogrostoid dominants is in general habit with buffalograss being a sod-forming shortgrass with long stolons while blue grama is largely a bunchgrass (cespitose or tufted) that sometimes forms a relatively large matlike growth from short rhizomes (Hitchcock and Chase, 1951, ps. 540, 545; Gould, 1975, ps. 351; 355, Shaw, 2008, ps. 89, 99). Aboveground growth features of blue grama were reported in a classic paper from the Central Plains Experimental Range (Turner and Klipple, 1952). In this author's experience blue grama more frequently grew in this mat (semi-sodforming) form on this and surrounding ranges of the Central High Plains than on ranges in the Southern High Plains where it consistently grew in the more chatacteristic cespitose habit. The general rule is that blue grama is a bunchgrass whereas buffalograss is a sod-forming grass, but there is considerabale phenotypic plasticity so that blue grama has more of a semi-sodforming shortgrass in the Central and Northern Great Plains, especially under heavier grazing (Wynia, 2007).

In addition--or as a corollary--to general morphology or growth habit of these two shortgrass species there have been several general studies into their general biology or natural history as well as specific characteristics. One of the characteristics of range grasses that was once widely studied involvedd characterizations of height-weight relations often expressed as height:weight ratios, especially as related to utilization or degree of use (Cook et al., 1962, ps. 114-119). Cook et al. (1962, ps. 115, 118) reproduced two figures showing this relationship in blue grama (Figure 3) and blue grama and buffalograss (Figure 7). With light to moderate grazing threr is proportionately greater weight in seed stalks (sexual shoots) of blue grama than in buffalograss, Turner and Klipple (1952) found that contribution of sexual portions of tillers in blue grama varied by a factor of 2.5 (10-25% of aboveground biomass) in different years.

In general growth habit and and time of flowering the co-dominant shortgrasses, both warm-season species, complemented each other and timed their phenological development so as to minimize--to some degree--overlap in time and space thereby reducing interspecific competition.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

112. Expanse of shortgrass- Two landscape-scale scenes of blue grama-buffalograss shortgrass plains range. On the "tight land" of shallower soil, especially of the surface layer (Soil conservation Service, 1982) than that of range sites represented above (Loamy Plains range site) and below (Sandy Plains range site) the two co-dominant shortgrasses, buffalograss and blue grama, comprised a substantially greater proportion (cover, apparent biomass, general abundance) of the range plant community. That difference (proportionately more shortgrass than midgrass species) did not appear to be due wholly to range site. The range introduced here and described in several subsequent photographs appeared to be--at least in part-- a grazing disclimax were long-term heavy grazing had reduced relative cover and herbage of midgrass species and where there was much greater portions of annual forbs.

This conclusion was based not so much on lesser portions of needle-and-thread (a species whose favored habitat is sandier soil) or western wheatgrass that thrives best in lower-lying einvronments like swales, but in the much greater cover of plains pricklypear and, even more so, on cover and density of annual invaders, most notably woolly or bristle-bract plantain (Plantago patagonica) and common, dense-flower, or prairie pepperweed (Lepidium densiflorum). Woolly plantain is vriable in life span ranging from the typical annual through biennial to short-lived perennial (McGregor et al. (1986). Both of these are native species, but they have invariably been recognized as opportunistic species (eg. on waste grounds) and indicators of disturbanceare as for instance by McGregor et al. (1986) and Weber (1990). In addition, western wheatgrass, the major midgrass species on this range, had received much greater utilization than the two shortgrass dominants on the range that was being (and, in the past, had been) grazed rather heavily to a fairly uniform stubble height.

One of the most widely cited stocking rate papers ever published was that for blue grama range conducted on the Central Plains Experimental Range (Bement, 1969).

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Shaly Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

113. Shortgrass vegetation and a sample of its turf- Transect-scale scene of blue grama-buffalograss shortgrass plains grassland (first slide) and local or quadrant scale view of the sward of this shortgrass range (second slide) under current moderately heavy (stocking was between moderate and heavy rates). In the second photograph almost all of the standing crop was blue grama and buffalograss. The latter was at peak standing crop and full anthesis whereas blue grama had not commenced elongation of sexual shoots.

Physiogonomy and structure of this semiarid, plains grassland as shown in the first of these two slides and the two immediately preceding slides (especially the second) revealed that this range vegetation could be interpreted as a shrub-shortgrass savanna in which the proportionately high cover and density of plains pricklypear showed this low-growing woody plant to be an associate species. Western wheatgrass was overall the distant third abundant grass on this range. Given the relatively uniform height to which this range herbage had been grazed western wheatgrass, a midgrass species, had been defolited to a much greater degree of use than those of the two dominant shortgrasses. This was one of the major reasons why this author concluded that this grassland vegetation was--to some extent--a grazing disclimax and not solely the product of this shallow-soil "tightland" range site. Bottlebrush squirreltail was also conspicuous on this range at this time, but it was widely scattered and less abundant than western wheatgrass.

Forbs on this range varied from stiff greenthread, conspicuous in the vernal society, scarlet globemallow, fringed sage, denseflower pepperweed, woolly or bristle-bract plantain, and spreading fleabane (Erigeron divergens). These forb species were presented in the next two two-slide sets.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Shaly Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

114. Patches of retrogression- Two "photoquadrants" of a blue grama-buffalograss-dominate plains grassland (or, perhaps more descriptively, a shortgrass-shrub savanna) on a limely upland that was--in part--a grazing disclimax. In addition to the two shortgrass dominants and plains pricklypear (which resulted in a savanna or savanna-like physiogonomy/structure) there were a number of forbs, both annual and perennial, on this range. Forbs were the "center of attention" in these shots. The first photograph presented fringed sage, scarlet globemallow, and woolly plantain while the second slide showed wooly plantain, scarlet globemallow, and spreading fleabane along with the conspicuous though widely scattered bottlebrush squirreltail. Also in the second photograph (lower right foreground) was a cute specimen of green-flowered hedgehog cactus (Echinocereus viridiflorus).

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Shaly Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

115. Spots of annuals- Local spot grazing in a blue grama-buffalograss shortgrass range in the Central High Plains. These were two grazing-induced microhabitats site Even within a grazing disclimax there can be spot grazing resulting in even more range degradation (retrogression) at this microscale, microsites of severe overgrazing. The first of these two "photoquadrants" featured both denseflower or plains pepperweed and wooly or bristlebract plantain. This latter forb was the "star attraction" of the second "photoquadrant". Shoots of blue grama and buffalograss were also present in both photographs.

These species like several of the others on this shortgrass range were presented and described below. Relatively high density and foliar cover of these two invaders (not to mention plains pricklypear) was one of the major reasons why this range worker concluded that the vegetation existing on this range was partially a gracing disturbance climax and not simply an edaphic climax.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Shaly Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

116. Stockers on shortgrass- Steers on late-spring blue grama-buffalograss upland range at outer edge of a sacrific area around a water tank. The dominant range species were blue grama and buffalograss. Scarlet globemallow and kochia (Kochia scoparia) were the major forbs (in that order). Plains pricklypear was very limited, but there was considerably more cheatgrass than on adjoining ranges, including other shortgrasss prairie and savanna, mixed prairie, and needle-and-thread--fourwing saltbush savanna.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Shaly Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

117. Range site variant- Mixed prairie on a soil higher in clay along the bench of a local draw or drainage in the Central Great (High) Plains. Rangeland shown here was Clayey Plains range site in contrast to Loamy Plains, Limy Plains, and Sandy Plains sites presented elsewhere in this section. This was a more mesic habitat than the Loamy Plains and Limey Plains range sites. Dominant species were needle-and-thread on slopes and western wheatgrass on floor of draw. Blue grama and buffalograss were associate species. There was more bottlebrush squirreltail than on the other range sites. Fourwing saltbush (Atriplex canescens) was the dominant shrub that replaced plains pricklypear that was the major woody species on Loamy Plains and lImey Plains range sites. Forb species were most of the same as described--most notably fringed sage, stiff greenthread, and scarlet globemallow--with the additions of Rocky Mountain bee plant or pink cleome (Cleome serrulata) and Astragalus adsurgens var. robustior known variously as tufted, purple, prairie, or standing milkvetch. The annual invaders, dense-flowered pepperweed and woolly or bristle-bract plantain, were very limited and there was no kochia.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 Plains Grassland Ecosystem). K-58 (Grama-Buffalograss). SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Clayey Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

118. Tufted midgrasses to sodforming shortgrasses- A fenceline contrast (first slide) and general view of a stocker range (second slide) on a High Plains mixed grass-fourwing saltbush savanna. Immediately outside this perimeter fence the relict grassland-savanna vegetation was needle-and-thread, Indian ricegrass, and western wheatgrass with lesser cover and biomass of blue grama and buffalograss whereas the range plant community grazed by stockers at moderate to fairly heavy stocking rates was overwhelmingly blue grama and buffalograss. Important specification: this was not a matter that under this degree of use (pasture-wide and ignoring varying utilization rates of different species) midgrasses like needle-and-thread, Inidan ricegrass, and western wheatgrass were grazed to a stubble height similar to that of blue grama and buffalograss. No, the three midgrass species were not just utilized to greater propotions; they were much less abundant and, in fact, locally absent from the stocker pasture. These taller bunchgrasses had been reduced in abundance and, in some local areas, grazed out.

Longterm grazing use at whatever the stocking rate(s) had been and currently was had converted this range vegetation from a mixed prairie-savanna of three midgrasses and two shortgrasses to a predominately two-species shortgrass community. Had this photograph been taken a month later aand after current peak standing crop of the three midgrass species and buffalograss and, instead, at peak standing crop of blue grama the relative cover and botanical composition would have been the same as at the time of this photograph. For that matter, the physiogonomy of both grazed and ungrazed portions would have been similar because differences in adult height of blue grama where protected (outside the fence) and that of more closely grazed blue grama on the range would still furnish the same contrast in height, and in mixture of cespitose and sodforming species (outside the fence) and predominately sod-forming habits of shortgrasses (on the grazed range). (Recall from above that at this more northern latitude, and in contrast to the Southern High Plains, blue grama produces more of a matlike growth habit, especially under heavier grazing.) At this time in the annual growth cycle of grasses four of the five major grass species were either at or approaching peak growth and development. There were four phenological stages present: 1) :immediate pre-bloom, western wheatgrass; 2) mid-bloom, Indian ricegrass; 3) peak anthesis, buffalograss; and 4) soft-dough grain stage, needle-and-thread.

Note the small size of closely browsed fourwing saltbush in right foreground of the second slide which was compared to fourwing saltbush plants growing on a more moderately grazed range presented in the next three photographs. This moderately grazed range was directly across a section line road which separated it from the range shown in these two photographs.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass) converted to K-58 (Grama-Buffalograss). SRM 608 (Wheatgrass-Grama-Needlegrass) converted to SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

119. Mixed grass-fourwing saltbush savanna- A mixed prairie grassland composition of blue grama, buffalograss, needle-and-thread, Indian ricegrass, and western wheatgrass with cover and density of fourwing saltbush (along with the nearly always-present plains pricklypear) so as to constitute a midgrass-shortgrass-savanna in the semiarid Central High Plains. The range presented in these three photographs was straight across from--and the same range site as--the more heavily grazed range shown in the two immediately preceding photographs. These two pastures were on opposite sides of a section line road.

The two major shortgrass species, blue grama and buffalograss, were the obvious co-dominants on this as on the heavier grazed range across the road, but these two were much less predominant on this lighter grazed pasture. Said another way, range vegetation seen here did not have proportions of the three major midgrass species (needle-and-thread, Indian ricegrass, and western wheatgrass) that were as great as those in the strip of relict vegetation outside the fence (as shown in the preceding slide set), but proportions (relative cover and biomass) of these three were was much higher than in the more heavily grazed stocker range across the road.

Cover and biomass of the three midgrass species were glaringly greater next to and within interspaces among shrubs, especially the larger fourwing saltbush plants. The main forb was scarlet globemallow.

Finally, students should notice all the plants of fourwing saltbush were much larger on this range with lower degree of use than on the more heavily stocked range on opposite side of the road. (This was very pronounced even with three different camera-to-subject distances.)

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect).FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass) converted to K-58 (Grama-Buffalograss). SRM 608 (Wheatgrass-Grama-Needlegrass) converted to SRM 611(Blue Grama-Buffalograss). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Loamy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

120. Savanna in low sand plains- Landscape-scale panarama of a mixed prairie with fourwing saltbush as dominant shrub and plains pricklypear as associate woody speceis forming a savanna in the Central High Plains. The herbaceous components (or "phase"), which was almost exclusively grass species, was textbook mixed prairie with a shortgrass element (blue grama and buffalograss), midgrass element (needle-and-thread, Indian ricegrass, western wheatgrass, and sand dropseed being the major species), and a tallgrass element represented by prairie sandreed (Calamovilfa longifolia). The grasses of this range community thus consissted or or comprised three layers. Forbs were quite limited and sporadic in distribution, but even these included a short-growing species, scarlet globemallow, and mid-height forbs including stiff greenthread, plains prickly poppy (Argemone polyanthemos), and veined dock (Rumex venosus) so that there were two erratic or interrupted forb layers. The two major shrubs also comprised two layers these being an intermediate-height shrub, fourwing saltbush, and a ground-level shrub, plains pricklypear. There were a few (very few) plants of broom snakeweed (Gutierrezia sarothrae) that grew to heights between those of fourwing saltbush and plains pricklypear. This sums to a total of seven layers of range vegetation (three of grass, two of forb, and two of shrubs), a remarkable stratification for this grassland/savanna (a mixed grass-shrub savannah).

Seasonal societies are very pronounced on this range type (or subtype). Seasonal societies are those detrermined by or as seasonal aspects in which different plant species of a range type (a Clementsian association) "make their most vigorous growth, flower, and fruit at different periods of the growing season" such that there are, for example, prevernal societies, vernal societies, estival societies, and autumnal societies (Clements, 1936; Weaver and Clements, 1938, p. 97). In the Clementsian climax hierarchy a seasonal society of climax vegetation was designated as a sociation (Clements, 1936). Sociations were based on life cycles of major plant species, especially subdominants, the phenological development of which was seen to be determined by temperature more than other factors. In Clements' view sociations were most prominent and best developed in grassland with there usually being three sociations in mixed prairie (Clements, 1936).

On this range type (subtype) of sand plains mixed grass-shrub savanna the dominant grass species, which were the community dominaants, changed fron cool-growing to warm-growing season. The overall dominant cool-season species of this range vegetation was needle-and-thread and the overall dominant warm-season species was prairie sandreed. To be sure there were local dominants such as western wheatgrass in swales and blue grama on upland microsites having soil with less sand, but overall (averaged across the entire plant community) such species were subdominants to associates. Indian ricegrass and sand dropseed were other major--usually associate--grass species. Buffalograss was locally an associate to co-dominant species with western wheatgrass in low-lying areas such as swales. There were occasional plants of broom snakeweed.

This range plant community provided a fine example of the phenomenon of seasonal societies from the perspective of herbaceous dominants. The vernal society was dominated and defined by the cool-season and fsstucoid species, needle-and-thread, whereas the estival (at least later in summer) through autumnal societies were dominated by the warm-season and eragrostoid species, prairie sandreed. Blue grama--another warm-season, eragrostoid grass-- was the associate to subdominant grass with prairie sandreed. Prairie sandreed is a tallgrass (and generally large) species while blue grama is a midgrass. Both of these species are rhizomatous, but rhizomes are longer in prairie sandreed so that it is a superior sand-binder.

This range vegetation was mixed prairie which would place it in the Forest-Range Environmental Study (FRES) unit number 38 (Plains Grasslands) as shown by Garrison et al. (1977), but the closest Kuchler System Equivalent that fit this mixed prairie form, dominance type/subtype, (or whatever vegetational level it is) so as to accomodate needle-and-thread as cool-season dominant and prairie sandreed as warm-season dominant was Nebraska Sand Hills Prairie or K-67 as shown in Garrison et al. (1977). Interpretation of this sand plain, or "flat" ("low") dunes, as a "vegetational island" of the Sandhills was consistent with the description by the Society for Range Management (Shiflet, 1994) of rangeland cover type SRM 603 (Prairie Sandreed-Needlegrass) which included the type in northeastern Colorado and southeastern Wyoming as well as the Nebraska Sandhills. Garrison et al (1977) plaaced Kuchler Equivalent 67 under FRES No. 39 (Prairie Grassland Ecossytem) which explained the slight discrepancy below.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 39 (Prairie Grassland Ecosystem). Variant or island of K-67 (Nebraska Sand Hills Prairie). SRM 603 (Prairie Sandreed-Needlegrass). Brown et al. (1998, p. 40) description: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Sandy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

121. Principal players on a sand plains savanna- Needle-and-thread, the general or overall cool-season dominant of a mixed prairie savannah, at peak standing crop and in soft-dough grain stage of development with fourwing saltbush, the major shrub species, in the Mixed Prairie Region of the Central High Plains. Prairie sandreed, the warm-season dominant of this range vegetation was still in early spring growth as was blue grama. Indian ricegrass was a local associate on habitats of deeper sands like that shown here.

A few younger (smaller) plants of broom snakeweed were in left foreground.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 39 (Prairie Grassland Ecosystem). Variant or island of K-67 (Nebraska Sand Hills Prairie). SRM 603 (Prairie Sandreed-Needlegrass). Brown et al. (1998, p. 40) descraiption: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Sandy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

122. Close-knit players- Needle-and-thread, cool-season dominant, and Indian ricegrass, associate species, with fourwing saltbush and plains pricklypear (first slide) and needle-and-thread and fourwing saltbush "joined at the hip" (second slide) as dominant herbaceous and woody species, respectively, in the vernal society of a mixed grass-shrub savana on a sand plains environment in the Central High Plains.

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 39 (Prairie Grassland Ecosystem). Variant or island of K-67 (Nebraska Sand Hills Prairie). SRM 603 (Prairie Sandreed-Needlegrass). Brown et al. (1998, p. 40) descraiption: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Sandy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

123. Stockers on a sand swale- A swale or wide, shallow drainage in a sand plains mixed grass-shrub savanna in the Central High Plains being grazed by long-yearling steers. The dominant range plant in the swale was western wheatgrass with buffalograss a local associate species. Rangeland along the swale (from slopes outward) was dominated by needle-and-thread in this spring aspect/spring society with fourwing saltbush the local associate to co-dominant species. Prairie sandreed (still at early phenological development at this time) was the herbaceous, warm-season dominant. Blue grama, Indian ricegrass, and sand dropseed were other important grasses. The most plentiful--though uncommon--forb was fringed sage that was conspicuous in the bed of the swale. There were also local patches with colonies of veined dock (Rumex venosus) in disturbed microsites such as local wash spots in the drainage (swale).

Central Plains Experimental Range (Agricultural Research Service), Weld County, Colorado. Mid-June (late vernal aspect). FRES No. 39 (Prairie Grassland Ecosystem). Variant or island of K-67 (Nebraska Sand Hills Prairie). SRM 603 (Prairie Sandreed-Needlegrass). Brown et al. (1998, p. 40) descraiption: Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. Sandy Plains range site. High Plains-Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado.Mid-June (late spring), early bloom stage.

125. Not a purple cow, but purple milkvetch- Purple, prairie, tufted, rattle, or standing milkvetch (Astragalus adsurgens var. robustior), and there are probably several other common names out there just waiting to be milked. There are a "gazillion" Astragalus species on the Western Range. Weber (1990, ps 183-188) listed almost 40 species of Astragalus for the eastern slope of Colorado. This is one of the more common species. These plants were growing in a moist draw on a range that had received light livestock grazing, at least in the current growing season.

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado.Mid-June (late spring), full-bloom stage.

126. Purple standing on the short prairie- Inflorescence of purple, prairie, standing rattle, or tufted milkvetch. Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado.Mid-June (late spring), early bloom stage.

127. Plain pepper- Common or prairie pepperweed (Lepidium densifolium) on grazing disclimax shortgrass plains range. This was one of the major forbs on the buffalograss-blue grama range described above. It was frequently the local dominant plant. This annual crucifer is one of the classic indicator species of overgrazing or other disturbances, and on a diverse array of range plant communities.

The short, rounded fruits of this species are of the fruit type known as silicles, cruicifer fruits that are relative short in comparison to their length.

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado. Mid-June, early fruit-ripening stage of phenology.

128. Plain plantain- Wooly plantain or wooly Indianwheat (Plantago patagonica) was the other major forb on the buffalograss-blue grama grazing disclimax range described above. This annual, like about all other Plantago species, is a weed, both economically and ecologically. Wooly plantain is an invader and an obvious indicator species of disturbance such as overgrazing. Cause of the denuded microsite seen here was known but to God, but it was a textbook example of this native, pioneer range plant successfully invading "new land" and, thereby, setting the stage for revegetation of the denuded spot via secondary plant succession.

Fortunately, most of this range that had obviously been subjected to overuse for "quite a spell", was not to the state of degradation (= stage of retrogression) as was this microhabitat. Still, and even without complete baring of the soil surface, there was more than enough grazing abuse for this unpalatable range forb to have a nice home along with its "extended family" (ie. a healthy population of P. patagonica). Wooly plantain was also successful in establishing itself over much of this range where existing vegetation was less drastically impacted. Wooly plantain is not restricted to overgrazed ranges. Abundant populations can also be found, when growing conditions have been favorable, on properly grazed ranges. However, wooly plantain is generally unpalatable and eaten by livestock mostly when little else is available. It is a classic invader in the model of Clements (1920) and Dykersterhuis (1949). Stubbendieck et al. (1992. p. 387) described wolly Indianwheat as being good forage for sheep for which it can be "a major forage species on lambing rnges".

This warm-season forb also "established" itself in the range plant literature earning spots in the old standby Range Plant Handbook (Forest Service, 1937, W150), the popular Pasture and Range Plants (Phillips Petroleum Company, 1963, 2003), Notes on Western Range Forbs (Hermann, 1966, p. 271), and by earning a place on the 200 species Master Plant List for the International Range Plant Identification Contest, North American Range Plants (Stubbendieck et al., 1992, ps. 386-387). Perhaps the main attribute for making such a "big hit" was the extremely wide distribution of this species that extends from some the Canadian Maritime provinces to British Columbia and south deep into the Republic of Mexico (see above references).

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado. Mid-June, peak-bloom stage of phenology.

129. Wooly range wheat- Shoots (first slide) and inflorescences (second slide) of wooly Indianwheat or wooly plantain on a shortgrass (buffalograss-blue grama) distirbance climax. range. This was on an upland and "tightland" (versus sandy) form of mixed prairie under extreme semiridity. The common name Indianwheat was supposedly derived from the Indian practice of gathering the ripe seeds as a food source. But then again, was there anything the Indians did not eat over much of their hardscramble habitat? Most livetock and wildlife do not eat it.

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado. Mid-June, peak-bloom stage of phenology.

132. Spreading across shortgrass- Spreading fleabane (Erigeron divergens) on a grazing disclimax form of shortgrass plains. There are various Erigeron species native to the Great Plains and closely adjacent regions like the Colorado Piedmont and San Luis Valley. Two more of these are Engelmann's fleabane (Erigeron engelmannii) and tufted fleabane (Erigeron caespitosus), the latter of these was shown and described below while the former was included with species of the black greasewood scrub treated in the Miscellaneous Shrubland chapter of Range Types. All of these are occasional rather than dominant or even associate composite forbs. They do provide a good example of speciation.

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado.Mid-June (late spring).

133. Something besides white or yellow- "Almost all" composites have heads with white or yellow petals so the purple corollas of tansey aster or tanseyleaf aster (Aster tanacetifolius= Machaeranthera tanacetifolia) afforded a proverbial welcome departure here on the grazing disclimax of a shortgrass plains range. OK, its weedy little beggar, but what the heck. A little variety with the buffalograss can't hurt too much. Besides these floral folk were holding their own smack dab in the middle of a black-tailed prairie dog (Cynomys ludovicianus) town. That's worthy of picture in itself.

Weld County, Colorado. Mid-June (late spring).

134. Green with envy- Green-flowered hedgehog cactus (Echinocereus viridiflorus) in its sexual prime. This cute little specimen was growing on the more-or-less manmade (disclimax) shortgrass plains of the Central High Plains described above. Most of the grass surrounding this cactus was blue grama with buffalograss second.

Echinocereus species are in Cactaceae subfamily Ceroideae.

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado. Mid-June, peak-bloom phenological stage.

135. Rocky Mountain bee plant or pink cleome (Cleome serrulata)- This annual forb of the caper family (Capparaceae) was growing in a moist draw on the deeper soil of an upland range in the Central High Plains. Its neighbors included the milkvetch known by such adjectives as purple, prairie, tufted, rattle, or standing (shown above) as well as wild alfalfa or scurfpea, blue grama, buffalograss, needle-and-thread, red threeawn, and sand dropseed.

In addition to the many colorful flowers borne in racemes, the trifoliate leaves (three leaflets) make this range forb readily identifiable and prominent on the Great Plains landscape.

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado. Mid-June, peak-bloom phenological stage.

136. One that can be stuck in anywhere- Local stand of scarlet globemallow (Sphaeralcea coccinea). One of the most common and widely distributed forb on mixed prairie through shortgrass plains grasslands is this member of the Malvaceae, mallow family. This bunch was growing on a green needlegrass-dominated mixed prairie range featured below, but millions just like it grew over the rest of western mixed prairie ranges (ie. this shot could have been just about anyplace in the Great Plains). Hermann (1966, ps. 179-180) reported that scarlet globemallow has a biological range extending from Alberta to Texas and into the Central Lowlands province as far east as Iowa with palatability varying from tremendously from poor (or even none) to good. Oddly, this species was not included in either the Range Plant Handbook (Forest Service, 1937) nor Pasture & Range Plants (Philllips Petroleum Company, 1963, 2003). Yet, there are countless acres of Great Plains grassland on which scarlet globemallow is the--as in the singlularly most abundant--range forb.

Scarlet globemallow is on the Master Plant List (of 200 species) of the International Range Plant Identification Contest sponsored by the Society for Range Management and described in North American Range Plants (Stubbendieck et al., 1992).

Washington County, Colorado. Mid-June (late spring), full-bloom stage.

138. Pale face on overgrazed mixed prairie- Pale or white evening-primrose (Oenothera albicaluis) growing beside scarlet globemallow (most leaves seen here). Both of these range forbs were growing on a black-tailed prairie dog town the ground of which had very few other species. Apparently prairie dogs do not care to eat (or even clip off) plants of these two species. O. albicaluiss is one of the more common evening-primroses on the Central Great Plains.

Weld County, Colorado. Mid-June, peak-bloom phenological stage.

140. Veined on the plains- Local colony of veined dock (Rumex venosus) on a "sandyland" (sand form) mixed prairie dominated by neede-and-thread. This was a modified or "semi-sandhills" subtype, a transition grassland intermediate between the classic sandhills and "hardland" (a less mesic range environment). Veined dock is one of the more chracteristic (and, certainly, conspicuous) range forbs on this variant of mixed prairie, especially on disturbed areas like degraded.range.

Agricultural Research eervice Central Plains Experimental Range, Weld County, Colorado. Mid-June, peak-bloom stage of phenology.

141. Prominently winged-Apices of sexual shoots of veined dock growing on a local denuded microsite on a variant of "sandyland" needle-and-thread dominated mixed prairie. The showy floral organs are gynoecia (singular, gynoecium) with fourunited carpels each of which is unilocular with one ovule. Mature fruit is a lenticular (three-sided) achene (Smith, 1977, p. 112). The uniquely pronounced winglike carpels are basis of another common name for this Rumex venosus, wild bignolia.

Agricultural Research Service Central Plains Experimental Range, Weld County, Colorado. Mid-June, peak-bloom stage of phenology.

142. Shortgrass Plains disclimax- A mixed prairie in far-western edge of Central Great Plains degraded to nothing but buffalograss and plains pricklypear. Cause of thee severe retrogression and range depletion was not known. Overgrazing is always a "chief suspect", but it is also possible that some ignorant (and euqllly daring or super-optimistic) sodbuster tried his hand at raising wheat on this marginal land. Regardless of cause, this was disturbance climax on shallow-soil, "tight land" the climax range vegettion of which was blue gram-buffalograss shortgrass plains. Local patches of blue grama were still present as, for example, in the small depression at far right midground.

Although the present vegetation on this deteriorated range was shortgrass-pricklypear, and the potential natural or climax vegetation is still only shortgrass (iel classic "shortgrass plains", it was included at this location (as well as in the Shortgrass Prairie chapter) because of it close spatial proximity to the actual mixed prairie range types.

This was a different range site from that of mixed prairie shown in the immediately preceding slide, but its physical closeness to that range justified placement of this sample of shortgrass prairie in this location within the mixed prairie chapter.

Weld County, Colorado. Late June. FRES No. 38 (Plains Grassland Ecosystem). K-58 (Grama-Buffalograss).SRM 611(Blue Grama-Buffalo Grass). Degraded state of Grama "Short-Grass" Series, 142.12 of Plains Grassland biotic community, 142.1 Brown et al. (1998, p. 40). High Plains- Moderate Relief Plains Ecoregion, 25c (Chapman et al., 2006).

143. Central Plains mixed prairie- Another Central High Plains example of the needle-and-thread--blue grama--western wheatgrass cover type, in this instance with a nd sagebrsh (Artemisia filifolia) comprising a pronounced shrub component. Plains pricklypear and soapweed yucca were distant second- and third-place shrub species. Other important grasses included sand dropseed, buffalograss, sideoats grama, red threeawn, squirreltail bottlebrush, scattered individuals of sand bluestem, and, of course (though quite limited), cheatgrass. .In this early estival society the most common forb was prairie or western spiderwort (Tradescantha occidentalis). Scarlet globemallow was sporadic in occurrence. Other forbs at this season were incidential composites like the wavyleaf thistle (Cirsium undulatum) which is a nonweedy (on range), short-growing, native perennial.

This range was obviously in high Good to Excellent range condition class depending on which part of the vegetation one chose to evaluate.

Central Plains Experimental Station, Washington County, Colorado. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006)

Transition grassland- The "tightland" or "hardland" mixed prairie of the Central Great (High) Plains with its various range sites is more diverse than it appears initially. The different grassland communities that developed in this semiarid continental climate are made up of various combinations of blue grama, buffalograss, western wheatgrass, sand dropseed, needle-and-thread, and green needlegrass. Miscellaneous other grasses included various bluegrass species, galleta, little bluestem, and little bluestem . The "sandyland" mixed prairie tends to have proportionately greater cover of midgrass species such as needle-and-thread, green needlegrass, and, of course, sand dropseed. There may also be more shrub cover on the grasslands that on soils higher in sand due to a more favorable soil water environment. This is most pronounced in the actual "sand hills" mixed prairie. Between these two general forms of mixed prairie, each of which has various range sites, there is a transition form of grassland--an ecotone--that itself has variations depending on soils, topography, aspect, as well as grazing history stretching to antiquity.

Some examples of this ecotonal form of mixed prairie were described in the following section.

144. Botanically rich mixed prairie- Landscape-scale perspective of an extremely plant species-rich mixed prairie in Central High Plains. On this cow-calf range major, native, perennial grass species included green needlegrass (Stipa viridula) and western wheatgrass which were co-dominants of this vernal society, blue grama, buffalograss, sideoats grama, silver bluestem, and few plants of sand dropseed.(ion that approximate order). There were some plants of the native annual grass, little barley, but very few plants of cheatgrass except in local disturbed areas such as around colonies of harvester ants and where spot grazing by cattle resulted in overgrazed microhabitats. Kentucky bluegrass (a naturalized, Eurazian perennial) grew on some of these locally disturbed patches of spot grazing that were less heavily grazed than those with kochia and cheatgrass.

Major forbs were in these disturbed microenvironments. The most abundant forb overall was the native scarlet globemallow. The associate forb (locally the second-most abundant on disturbed spots) was kochia (Kochia scoparia), a naturalized, Eurasian annual of the goosefoot family (Chenopodiaceae) or wild alfalfa or slender scurfpea (second-most abundant on undisturbed or less disturbed mini-locations).

This range was in high good to, probably, Excellent range condition class. It was a textbook example of the diverse range vegetation of climax mixed prairie.

As to taxonomy of this native vegetation this range plant community had the same designations as those described immediately above, but the Stipa species was different and there was not a shrub component on this variant of midgrass-dominated mixed prairie.

Washington County, Colorado. Mid-June (late vernal aspect; (peak standing crop of the vernal society). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

145. Height of the cool-season dominants- Peak standing crop of green needlegrass and western wheatgrass, cool-season co-dominants of a mixed prairie which also ncluded other native perennial grasses ranging from blue grama, buffalograss, sideoats grama, silver bluestem, and sand dropseed (in that relative order) as well as little barley, native annual grass, and the forbs, scarlet globemallow (the most sbundant), kochia, and wild alfalfa.

Local stands shown in these two "photoquadrants" were ungrazed being on highway right-of-way just outside the grazed range introduced in the preceding photographs. The vast bulk of biomass in this sward was green needlegrass and western wheatgrass: conservatively two-thirds to three-fourths of peak standing crop in the vernal society. In the estival or autumnal society dominated by warm-season season grasses (blue grama, buffalograss, sideoats grama,etc.) blue grama will be the dominant and provide a much greater proportion (percentage) of biomass as well as cover. In a really "mixed" mixed prairie like this one, dominance is season (society)-specific as well as site-specific. It seemed obvious that the greatest peak standing crop on this variant of mixed prairie would be during the vernal society because the two cool-season dominants are substantially larger (ranker-growing) than the dominant warm-season grasses plus these warm-season species had achieved much of their shoot growth by this time. For instance, buffalograss was in full-bloom and, though regarded as a warm-season shortgrass, was near its peak biomass.

This mixed prairie vegetation could be interpreted as classic mixed prairie not only on basis of tremendous botanical diversity and mix of cool-season and warm-season species, but also as to structure because green needlegrass of the stature attained on this range could be regarded as a tallgrass species. On some sites (and doubtless in drought years) green needlegrass barely attains mid-height and would be viewed as a midgrass, but at adult plant height of peak standing crop at time of these photographs green needlegrass stood over three to three and half feet tall. Green needlegrass can grow to heights equal to or greater than those of little bluestem (Shaw, 2008, ps. 231, 543)

Washington County, Colorado. Mid-June (late vernal aspect; (peak standing crop of the vernal society). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

146. Ain't all tall, green, and lush- Two examples of spot disturbance on the green needlegrass-western wheatgrass-blue grama-buffalograss mixed prairie cow-calf range introduced above. The first example (first slide) was at edge of a "bed" (colony) of western harvester ant (Pogonomyrmex occidentalis). The second example (second slide) was of heavy spot grazing by beef cattle. Major plant species at both degraded spots were scarlet globemallow (#1) and buffalograss (#2). In addition kochia was common near the entrance to the harvester ant nest.

Washington County, Colorado. Mid-June (peak bloom for both scarlet globemallow and buffalograss).

147. Cows prefer kochia- Selective grazing by cows and calves on green needlegrass-western wheatgrass-blue grama-buffalograss mixed prairie in the Central High Plains. This is the same cattle range described immediately above. In this "photoplot" cattle were able to exercise their preference for Kochia scoparia by grazing it to exclusion of scarlet globemallow and buffalograss. The latter two species grew immediately adjacent to (literally in contact with) kochia, which was consistently "topped" while scarlet globemallow and buffalograss were untouched.

Kochia is a now-naturalized, Eurasian, annual chenopod that is usually considered a weed particularily in regard to field crop production. However, it is well-known that kochia is a palatable forb. In fact, kochia is sometimes planted and grown as a forage field crop or managed as a self-seeding annual forage. On ranges, such as the one described here, kochia is frequently more palatable than many (if not most) native plants.

Kochia scoparia as an introduced forage species was treated in the chapter, Introduced Forages.

Washington County, Colorado. Mid-June (late vernal aspect; (peak standing crop of the vernal society). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006).

1

A need for clarification- Classification of mixed prairie--in fact, of Great Plains grasslands in general, remains in need of greater specification and explanation. Neither mapping of potential natural vegetation by Kuchler (1964, 1966) nor descriptions of rangeland cover types (Shiflet, 1994) were detailed or inclusive enough to include major, widespread climax range plant communities. The two major reasons for this are:1) intricate patterns edapho-topographic climaxes that would be difficult to present at the larger, more general (= zonal) mapping scales used and 2) climax types that have seasonal (essentially cool- and warm-season) dominants so that it is not possible to have accurate type designations when cover (dominance) type names include only dominants of one season (ie. cover type names include only dominant species of one phase of the annual growing season).

The Kuchler unit 58 or 65 (Bouteloua-Buchloe; Blue Grama-Buffalograss), depending on which map version of potential natural vegetation is used, is the largest and most obvious example of this problem. Blue Grama-Buffalograss is one of the largest of the Kuchler (1964, 1966) units, but within this regional (zonal) natural vegetation there are numerous units of potential natural vegetation of smaller size (spatial coverage) and, hence, greater difficulty of mapping that are dominated by other grass species. One of the more widespread and conspicuous of these is mixed prairie dominated by festucoid (cool-season) grasses such as needle-and-thread and/or Indian ricegrass on deeper, sandier soils and . Another range type dispersed within the regional Blue Grama-Buffalograss unit is Wheatgrass-Needlegrass (unit 59 or 66, including western wheatgrass-grreen needlegrass which, contrary to Kuchler (1964, p. 66), does include the latter in Colorado (see slides below).

These map units would appear as irregular-shaped, pokadot-like figures mostly within the surrounding regional blue grama-buffalograss vegetation, the "shortgrass country". In the terminology of Landscape Ecology Stipa-Oryzopsis units are patches in a matrix of Bouteloua-Buchloe. The floristically related Kuchler (1964, 1966) unit of 63 or 70 (Sandsage-Bluestem Prairie) was mapped near edges of and within the zonal shortgrass vegetation. This same general pattern would appear with smaller, but more numerous "spots" of Stipa-Oryzopsis if Kuchler (1964, 1966) had recognized this potential natural vegetation as a mapping unit. He did not (probably because he did not show units of vegetation at that small a mapping size or scale) though he did designate three units of potential natural vegetation which included Stipa comata as a dominant. (Kuchler, 1964; ps. 63, 64, 66). Likewise there would be smaller areas of map Kuchler unit 59 or 66 (Agropyron-Stipa) inside the unit 58 or 65 that also illustrated the problem presented by "islands" of one unit of potential natural vegetation within zonal- (= regional-) scale potential natural vegetation or, in context of the polyclimax or climax pattern theories, edapho-topographic climaxes within a climatic climax.

The problem presented by presence of two species of dominants or two sets of dominants (one for cool- and one for warm- growing seasons) in the same climax community was not addressed by Kuchler (1964, 1966). This phenomenon does not occur in many grassland cover types, but it is a feature of some dominance types and Kuchler units. One of these which was shown and described below had blue grama and buffalograss (eragrostoide grasses) as the warm-season dominants while needle-and-thread, sometimes, with Indian ricegrass (both festucoid grasses) were cool-season dominants. Some of the large area mapped by Kuchler (1964, 1966) unit 58 or 65 (Bouteloua-Buchloe) would be more accurately described as Stipa or Stipa-Oryzopsis (cool season)/Bouteloua-Buchloe (warm season). Such a lenghty designation (title) would appear awkward, but it would correctly show that dominance in such natural vegetation is by season (ie. has an aspect component). Influence (such as reaction in the Clementsian model) of some major range plant species would be more seasonal than yearlong. In this example, buffalograss presents something of a unique case because although it is an eragrostoid, and thus regarded as a warm-season, species it often has a bi-seasonal or opportunistic flowering pattern such that it blooms simultaneously with both needle-and-thread, Indian ricegrass, and/or western wheatgrass as well as with blue grama and some of the panicoid species like the bluestems. In such range vegetation buffalograss, the major sod-forming grass species, is an obvious dominant, especially when viewed as dominance (= cover) types where the criterion for dominance is plant cover, foliar or basal. The case for cover dominance is less obvious for bunchgrasses whether warm-seaon species like blue grama or cool-season species like needle-and-thread. With such cespitose species foliar or aerial cover, perhaps along with biomass (even if subconsciously), becomes more relevant. Nonetheless, there are clearly two-seasonal periods of dominance and two sets of dominants in certain grassland types, particular in mixed prairie where co-dominants are often a shortgrass and a midgrass species.

Another range type scattered--and not recognized-- through the Kuchler (1964, 1966) "shortgrass country" (unit 58 or 65; Bouteloua-Buchloe) was the prairie sandreed--needle-and-thread (Calamovilfa-Stipa) sandhills mixed prairie (Shiflet, 1994, p. ). In this rangeland type there is a a cool-season (festucoid) and a warm-season (eragrostoid) co-dominant. This is a textbook example that illustrated (in a most pronounced way) the phenomenon of aspect in range vegetation.

Frederic E. Clements clearly understood the aspect (seasonal) feature of vegetation. Aspect dominants or subdominants were shown in his vegetation classification scheme as the unit he labeled sociation or aspect society (Clements, 1936, p. 276). He explained that sociations were best developed in grasslands where seasonality is prominent with progression of the annual cycle from spring through autumn. There were commonly three sociations in mixed prairie for example. Dominants of the aspect society can be overall dominants when their presence (including during dormancy) is "controlling at all times" as for instance with some needlegrasses, wheatgrasses, and buffalograss (Weaver and Clements, 1938, p. 97).

In some Kuchler (1964, 1966) units of potential natural vegetation the aspect feature was critical to understanding the plant community, yet this feature was included only in description (perhaps in the list of "other [species] compnents") and not title of the unit. Importance of needle-and-thread, and even more so, Indian ricegrass in the "shortgrass country" (within the Bouteloua-Buchloe unit) was overlooked by Kuchler (1964, 1966) in the opinion of the current author. Unit 58 or 65 is considerably more diverse than mapped. Admittedly, it would be more difficult to map the spotted spatial pattern or mosaic of climax plant communities within this regional plains grassland than, by contrast, the long, narrow arrangement of forest vegetation in mountainous terrain. The fact remains that there are climax plant communities in the Southern and Central Great Plains that are dominated by needle-and-thread and/or Indian ricegrass which can be mapped as potential natural vegetation. Examples were presented in detail below. Indian ricegrass-dominated vegetation can be interpreted as semidesert grasslands so examples of this range type were cross-referenced in that chapter.

The sandhills range presented in the section immediately below was clearly dominated by needle-and-thread with blue grama as associate species. It was essentially missing a tallgrass (bluestem and prairie sandreed) component although individuals of these species were present. Perhaps tallgrass species had been grazed out although this seemed unlikely. Also a cold, wet, late spring over this region had retarded phenological development of warm-season grasses while resulting in a standing crop of needle-and-thread seldom seen. Conversely, species composition dominated by needle-and-thread and blue grama was consistent with the observation of Dodd (in Gould and Shaw,1983, p. 350) that these two species “are dominant in a limited number of areas with sandy soil”. Whatever the explanation, there was only miniscule cover of sand and little bluestems on this range. Range vegetation shown here was an island of mixed prairie characterized by sand sagebrush in a “sea” of  mixed prairie dominated by the shortgrasses, blue grama and buffalograss.  Range vegetation presented was obviously a variant of sand sagebrush prairie with range condition class (sucessional status) unknown.

Morgan County, Colorado.Late June, but spring-summer growing season was delay such that this was still vernal aspect (vernal plant society). FRES No. 39 (Prairie Grassland Ecosystem). K-63 (Sandsage-Bluestem Prairie).

152. Central Plains Sandhills mixed prairie- Landscape-scale view of needle-and-thread dominated-mixed prairie in sandhills of western High Plains. Blue grama was the associate plant species in this range vegetation in which there was no characteristic tallgrass species. Sand sagebrush provided an infrequent though defining shrub component in this range plant community. Plains pricklypear was the second important shrub species on this range. Species composition and structure of range vegetation was relatively limited and fairly simple (ie. not a range plant community of remarkable biodiversity). There was, however, a major warm-season and major cool-seaosn grass species so as to have pronounced differences in seasonal aspects and societies (even if simple). Also, just two major grass species resulted in both bunchgrass and sod- (sodforming) grass components as well as (by traditional usage) midgrass and shortgrass growth forms in this climax range plant community.

This range type was mixed prairie (of dominant and distinguishing midgrass and shortgrass species but without tallgrasses), and with infrequent shrub cover. This was grassland and not savanna; mixed prairie not tallgrass prairie (with distinction from the latter being critical and explained lower in this caption).

Nor was this range type a form of true prairie. Arguably this climax grassland could be intepreted and described as true prairie from the standpoint of dominance by needle-and-thread or as a transition form of prairie, but blue grama was present at such cover, density, and constance as to be always either an associate or, less commonly, co-dominant. Such constant presence and role of blue grama unquestionably placaed this grassland vegetation in mixed prairie, the Stipa-Bouteloua association (Clements, 1920, p. 135-139) and not in true prairie, the Stipa-Koeleria association (Clements, 1920, ps. 121-131). In this classic and seminal monograph there was a Stipa comata consociation listed for both true prairie and mixed prairie (Clements (1920, ps. 122, 137, respectively ), but a major role of blue grama (co-dominant or associate) as evidenced by a Boutelous gracilis consociation was limited to mixed prairie (Clements, 1920, p. 137). Furthermore, eleven lines below his listing of consociations, Clements (1920, p. 137) cited an earlier survey and description that placed grassland near Akron, Colorado in mixed prairie. Range vegetation presented here was photographed in the vicinity of Akron, Colorado.

Climate was also a distinguishing factor in defining this range type. Development of this climax vegetation in the sermiarid rather than the subhumid zone to the east was a major difference and a distinguishing feature that also placed this range type closer to mixed prairie than true prairie. Clements (1920, p. 122) drew the western boundary of true prairie to aproximately the 98th meridian. Range vegetation shown here was to the west of the 101st meredian well within the vegetational zone of true prairie (Clements, 1920, ps. 136-137).

It was also stressed that the land form and soils of these sandhills should not be confused with the Nebraska Sandhills which are located to the east and in a generally more moist precipitation zone. Range vegetation in the Nebraska Sandhills varies along isohytes (as well as among other environmental variables), but these various plant communities are primarily postclimax tallgrass prairie whereas climax vegetation of the sandhills to the west is mostly various types of mixed prairie. Likewise, there is a similar overall difference between the postclimax tallgrass prairie of the sandhills or duneland in the Southern Great Plains (as for example in northwestern Oklahoma) and mixed prairie of the sandhills shown here. There is an obvious unity of sandhills mixed prairie and sandhills tallgrass prairie both as to land form, soils, and plant species shared in common. Sand sagebrush was the most conspicuous of shared defining species. This was explained in the two rangeland cover type descriptions provided by the Society for Range Management (Shiflte, 1994, ps.74, 99) that could be applied--corrrectly and precisely-- to this needle-and-thread mixed prairie vegetation. Neither of these descriptions--in the current author's opinion--distinguished clearly between mixed and tallgrass prairie forms or variants within range types that justifiably (in this worker's view) could have been split into separate rangeland cover types for sand sagebrush-tallgrass prairie and sand sage-mixed prairie types.

Morgan County, Colorado. Late June- late vernal aspect; soft grain stage in needle-and-thread. FRES No. 38 (Plains Grassland Ecosystem). No appropriate Kuchler unit. SRM 605 (Sandsage Prairie) and/or SRM 722 (Sand Sagebrush-Mixed Prairie): two competing rangeland cover types or two slightly different titles and descriptions of the same or very similar range vegetation. Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Moderate Relief Plains Ecoregion, 25c (Chapman et al., 2006)

153. A western sandhills mixture- Vegetational mosaic of Stipa-Bouteloua mixed prairie on sandhills of the Central Great Plains. Local (separate) patches of needle-and-thread consociation (background) and blue grama consociation (foreground) with sand sagebrush providing a woody component to both. In this overall range plant community needle-and-thread was the dominant and blue grama the associate species. In local spots blue grama was the dominant, if not the exclusive, species (foreground, both photographs). Other grasses commonly (widely) associated with needle-and-thread and blue grama (eg. sand dropseed, buffalograss, sideoats grama, red and purple threeawns) were limited almost to point of nonexistance. The two major climax (decreaser) grasses did, however, furnish both warm-season and cool-season species to produce pronounced seasonal aspects and societies on otherwise simple (though never boring) species composition and structure of range plant community. These two species also contributed both a bunchgrass and sod (sodforming) grass and, by conventional terminology, a midgrass and a shortgrass. In effect, there was considerable diversity and variation as to life (growth) form and layers of vegetation for such a limited number of species and groups of range plants. .

Forbs were as limited and, in fact, of no obvious consequence. Shrubs were present as sand sagebrush, a definng species (eg. sand sage mixed prairie) though one more conspicuous than dominant as to relative cover, and plains pricklypear. As could be seen throughout this Mixed Prairie (as well as the Shortgrass Prairie) chapter, plains pricklypear was the single most consistently present or constant shrub on the semiarid grasslands of the Great Plains. This included being associated with more domiant grass species, on more soils (associations and/or series) and land forms, and in more ecoregions than any other woody plant.

Morgan County, Colorado. Late June- late vernal aspect; soft grain stage in needle-and-thread. FRES No. 38 (Plains Grassland Ecosystem). No appropriate Kuchler unit. SRM 605 (Sandsage Prairie) and/or SRM 722 (Sand Sagebrush-Mixed Prairie): two competing rangeland cover types or two slightly different titles and descriptions of the same or very similar range vegetation. Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Moderate Relief Plains Ecoregion, 25c (Chapman et al., 2006)

154. Needle-and-thread consociation in Central Plains Sandhills- Stipa comata is the number one dominant and the first defining species of the climax mixed prairie (Clements, 1920, Weaver and Clements, 1938, Dodd (in Gould and Shaw(, 1983). While difficult--if not impossible--to show conclusively, it is generally assumed from common observtion that heavier and more continuous (or frequent) commercial grazing has resulted in widespread increase in blue grama relative to the usually taller-growing needle-and-thread. It could be argued that such a shift from one climax co-dominant to the other did not amount to a change in successional status of range plant communities. Plus, any such change in relative cover (and consequently in species composition) from dominance by cool-season to warm-season grass was a major practical--an economically advantageous--change from the standpoint of range cattle production. With decreases in needle-and-thread and corresponding increases in blue grama, beef cattle could graze on better summer pasture (have nutritionally superior diets) when there is less risk of animal death (and tremendous economic losses) due to blizzards. There are at least two other obvious advantages of blue grama over needle-and-thread: 1) blue grama cures better for winter forage and 2) blue grama does not have the potential for mechanical injury to animals posed by the sharp callus on the lemma of needle-and-thread.

These facts of ranching notwithstanding, from an ecological perspective dominance of mixed prairie on many (probably most) range sites indicates range plant communities closer to the potential natural (pre-Columbian) vegetation. Dominance ("first among equals") by needle-and-thread indicates he successional "benchmark", the vegetation development "highwater mark" of some range types of mixed prairie and of mixed prairie in genera.

Such a state of climax range vegetation was shown in these two photographs, the first of which presented the general physiogonomy while the second gave detail of the sward of a needle-and-thread consociation. Presence of sand sagebrush as the major shrub of this climax mixed prairie community was also emphasized.

Emphasis was laid on three other points. First, these photographs were taken in a year that was extremely favorable for growth and productivity of Stipa comata A cold wet period from late winter through spring resulted in an "extra good year" and an extraordinary crop of biomass by needle-and-thread. Second, photographs were taken in late June at peak standing crop for needle-and-thread, a cool-season species, and before blue grama, a woarm-season species, had made more than mid-stage vegetative growth. This resulted in photographs that emphasized cover, density, and relative composition of the former more than the latter. Finally, this range professor and advocate of sound grazing land management had to mark the outstanding stewardship and obvious love of the land demonstrated by the owner and/or manager of this rangeland.

One of the goals of this publication was to highlight the best in stewardship of natural resources so as to provide students with outstanding examples of conservation and wise (proper) use management of the land. This example of needle-and-thread--blue grama mixed prairie in Excellent range condition class furnished a superb standard for which any range manager could strive. Cattle of quality equal to that of the range they grazed had just been gathered and the photographer was unable to show the principal tool by which this range was being cared for and left unimpaired for the landowner's grandchildren.

Morgan County, Colorado. Late June- late vernal aspect; soft grain stage in needle-and-thread. FRES No. 38 (Plains Grassland Ecosystem). No appropriate Kuchler unit. SRM 605 (Sandsage Prairie) and/or SRM 722 (Sand Sagebrush-Mixed Prairie): two competing rangeland cover types or two slightly different titles and descriptions of the same or very similar range vegetation. Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Moderate Relief Plains Ecoregion, 25c (Chapman et al., 2006)

155. Growing by bunches in the sandhills- Several plants of needle-and-thread on the sandhill range described in the above section. The cespitose (bunched or tufted) growth habit of this species was evident. These plants were in stages of both asexual (vegetative) reproduction and sexual reproduction: shoots (tillers only; no rhizomes or stolons) and fruits (caryopses), respectively. A top-down view of Stipa comata was given in the succeeding slide.

Morgan County, Colorado. Late June- late vernal aspect; soft grain stage in needle-and-thread.

156. Fulfilled and being fulfilled- Needla-and-thread at peak standing crop and with grain in soft-dough stage "accompanied by" plains pricklypear in full bloom. This "photo-quadrant" was on the "mint condition" sandhills range featured in this section and dominated by needle-and-thread and with blue grama as the associate species (Stipa comata-Bouteloua gracilis mixed prairie). Sand sagebrush was present as a defining--though certainly not a dominant--climax species of this range vegetation, hence the Sand Sagebrush Mixed Prairie rangeland cover type (SRM 722). Plains pricklypear was also a climax species of this needle-and-thread--blue grama sandhills range.

This photograph with plains pricklypear growing in a climax stand (a consociation) of needle-and-thread, the regional dominant species of mixed prairie, demonstrated the fact that plains pricklypear, like sand sagebrush, is a climax species of this rangeland vegetation. It must be strongly stated and clerly explained that these two woody species are native components of the climax or potential natural vegetation only at relative abundance (ie. general or overall density, cover, presence, biomass) that is natural, where natural is as a minor component. Excess abundance (excessive cover, biomass, density, etc.) of either of these two shrubs constitutes brush (noxious woody plants) invasion and is both symptom and partial cause of range degradation (= retrogression). The relative "amount", the percentage composition or proportion, of pricklypear or sagebrush is what determines whether these shrubs are native woody components of climax vegetation or brush. At the proportion of plains pricklypear preented here this would clearly be brush invasion, but this shrub was present overall in the plant community of this range at much lower relative cover and biomass than shown in this "photo-plot", the purpose of which was simply to show both the dominant grass (needle-and-thread) and plains pricklypear as native plants on sandhills mixed prairie.

This photograph also presented both species in sexual reproduction: plants of both species either fulfilled (plump, ripening caryopses of needle-and-thread) or being fulfilled (flowering stage as prelude to fruit and seed production in plains pricklypear). Life and annual cycles of both species were being completed; each species was perpetuating itself with "re-shffling" of the gene deck. The magic and mystery of life portrayed through range plants.

Morgan County, Colorado. Late June- late vernal aspect; soft grain stage in needle-and-thread.

157. Another and "purer" form- Another consociation of needle-and-thread on low sandhills with plants of sand sagebrush ""very few and real far between" and without a mosaic of local shortgrass and midgrass patches as in mixed prairie and mixed prairie-savanna shown above. This was not only the grassland (vs. savanna) variant or phase of mixed prairie it was also mixed prairie of strictly midgrass composition any appreciable cover of shortgrasses being absent from this range vegetation.

This simple range vegetation defied categorization as to published designations of rangeland cover types, range ecosystems, biotic communities, etc. It seemed plausible that past management, especially of grazing, had eliminated (probably through interactions with competitiveness and efficient reproduction, in particular seedling establishment, of needle-and-thread) other grass species. The most likely of these would have been prairie sandreed and blue grama. Perhaps heavy grazing later in summer (high stocking rates during the warm-growing season) and possibly with delayed or deferred spring grazing reduced the warm-seaon grasses while needle-and-thread (the cool-season dominant on this deep sand) received little if any grazing other than by smaller numbers of wildlife. Speculation on the part of a passing-through rangeman.

Anyway, number one, something happened; number two, it was a helluva stand of needle-and thread.

159. Stand of needle-and-thread- Consociation of Stipa comata on an Excellent condition class range in a more western part of the Central Great Plains. The genus Stipa, including all those split-out, cladistically invented genera in Barkworth et al. (2007), is one of the dominant and defining taxon of the once-great grasslands of the interior of North America. Clements (1920, p. 114) interpreted the climax vegetation of continental interior at the most extensive scale of a plant community as the Grassland Climax (Stipa-Bouteloua Fomation) which included six Associations, one of these being the subject of this chapter which is Mixed Prairie (Stipa-Bouteloua Association). S. comata was the Stipa species that defined (and furnished the first name for) the association of the mixed prairie in the Clementsian model (Clements, 1920, ps.135-139). Green needlegrass (S viridula) was also important and had its own consociation (Clements, 1920, p. 137) as was porcupinegrass (S. spartea), which was the equivalent dominant species of the True Prairie (Stipa-Koeleria Association). Yet it was S. comata that "headed the ticket" of the Mixed Prairie (proper name) as interpreted by Clements (1920, p. 122): "Stipa spartea is the most typical domiant of the true prairies, while S. comata belongs primarily to the mixed prairies". Nonetheless even on True Prairie one of the major consociations of the association was that of S. comata (Clements, 1929, p. 122).

Dodd (in Gould and Shaw, 1983, ps. 349-351) adopted and preserved in the basic Agrostology text the climax (association) interpretation of Clements, 1920). In addition, Dodd was more specific as to which species were dominants and associates on the general kinds of range sites. Weaver and Clements (1938, p. 523) listed needle-and-thread first as "major dominants of the widest distribution" of midgrass species in the mixed prairie.

Needle-and-thread is the plant, the number one--most major and first dominant--species (ie. the defining plant species) of the mixed prairie in the successional sense, "the alpha plant" of the mixed prairie climax; even though blue grama likely furnishes more feed for range animals as the mixed prairie currently exist.

Ecological sidebar: this same relationship also held for the pre-Spanish Pacific Prairie on which S. pulchra, purple needlegrass, was the one dominant of the association "which far overshadows all the others" (Weaver and Clements, 1938, p. 526). Stipa is one damn important genus in defining major units of North Amereican grasslands.

Laramie County, Wyoming. Late June; peak standing crop.

161. Whole plants (shoot portions) of needle-and-thread- Thye cespitose (bunched or clumped) habit of needle-and-thread was conspicuous in this photograph which also introduced the prominent panicles with ripening caryopses inside the long-awned lemmas. These latter features were shown immediately below. The individual plants shown here were relatively small for this species. These particular plants had established on a road cut made a few years earlier and these appeared to be young individuals (genotypes) of needle-and-thread. This seeding-in ability is another testament to the survuval and dominance qualities of this outstanding native species.

A good general and practical reference fo needle-and-thread was the Natural Resources Conservation Service Plant Guide (Ogle, 2006).

Niobrara County, Wyoming. Late June; peak standing crop.

163. Florets of needle-and-thread- The long-awned lemmas surrounding caryopses (grains) is a hallmark feature of needle-and-thread, the number one and major defining dominant of the mixed prairie. This is also a morphological characteristic that can inflict mechanical injury to grazing animals. This drawback does not override the forage value--both yield and nutritive content--of this climax species.

Laramie County, Wyoming. Late June; hard-dough stage.

164. Another important needlegrass- Stand of green needlegrass (Stipa viridula) on a postclimax tallgrass prairie in Nebraska.Sandhills. Green needlegrass is a midgrass species that is more typical of the mixed than of the tallgrass prairie. For that reason some photographs of S. viridula were included here even though the examples were, strictly speaking, growing on tallgrass prairie range. Clements (1920, p.137 ) recognized a green needlegrass consociation for his Mixed Prairie (Stipa-Bouteloua Association). Even though green needlegrass is a dominant on some mixed prairie range sites, it is needle-and-thread that is the defining overall dominant of the mixed prairie.

Fort Niobrara National Wildlife Refuge, Cherry County, Nebraska. Late June; grain-ripe phenological stage.

165. Representative of green needlegrass- A single plant of green needlegrass in the stand introduced in the immediately preceding slide was used to show habit and general features of this cespitose species.

The Natural Resources Conservation Service Plant Guide for green needlegrass (Knudson, 2005) was recommended as a semi-technical reference.

Fort Niobrara National Wildlife Refuge, Cherry County, Nebraska. Late June; grain-ripe phenological stage.

166. nflorescence of green needlegrass- Panicle on one of the plants growing in the stand on postclimax tallgrass prairie that was presented above.

Fort Niobrara National Wildlife Refuge, Cherry County, Nebraska. Late June; grain-ripe phenological stage.

167. Floral reminiscence of an arachnid resemblance- Western or plains spiderwort (Tradescantha occidentalis), Commelinaceae (dayflower family), on Great Plains mixed praririe. This monocotyledon is often the most common and locally dominant forb on mixed prairie ranges in higher condition classes. The specimen in the first of these slides was on a range featured below that represented the needle-and-thread--western wheatgrass cover type (SRM 607) whereas the specimen in the second slide was on a range described below that was as an example of mixed prairie of the western wheatgrass--blue grama--needle-and-thread type (SRM 608).

First photograph from Sioux County, Nebraska; second photograph from Washington County, Colorado. Late June, full-bloom stage.

168. Pretty on the plains- A plant of plains, bracted, or western spiderwort (Tradescantha bracteata) bearing an unusually prolific crop of blooms in an unusually wet spring on the Central Great Plains. Details of some of these inflorescences was shown in second photograph. This particular plant was growing in a sea of needle-and-thread.Tradescantha bracteata integrades with T. occidentalis so that it is almost impossible to distinguish between these two species.

Washington County, Colorado. Late June, peak-bloom stage.

169. About done for this year-A few plants of western or plains spiderwort that were "winding down" for this year's growing season. Fruit was ripening and shoots were senescing and about to enter dormancy. These plants were on climax western wheatgrass--ble grama--needle-and-thread-dominated mixed prairie where they were only one of several range forbs included in this section.

Niobrara County, Nebraska. Late June.

170. In Excellent company- A prime specimen of crested tongue penstemon (Penstemon eriantherus) on Excellent condition class mixed prairie of needle-and-thread, western wheatgrass, blue grama, Indian ricegrass, and threadleaf sedge. The range that this beauty was growing on was presented and described above. Some of the other range plant species growing on this same "mint condition" range (eg. threadleaf sedge) were shown below with other dominant or otherwise major range plants.

Niobrara County, Wyoming. Late June; full-bloom stage.

171. A crested tongue: what more could anybody want?- Up close views of the flowers of crested tongue penstemon growing on the Excellent condition mixed prairie range described above.

Niobrara County, Wyoming. Late June; full-bloom stage..

172. Narrowleaf (narrow-leafed) or narrow beardtongue (Penstemon angustifolius ssp. angustifolius)- This Penstemon species does not typically grow as large (or as showy) as beard tongue penstemon just shown, but it is another species of forb on the western part of mixed prairie. This one was also growing on a range described previously (and also in Excellent range condition class).

Sioux County, Nebraska. Late June; full-bloom stage.

173. Mixed prairie on the Central Great Plains- Diversity in several forms (species composition, cool-season vs. warm-season species, plant community structure, microrelief of land surface) was present on this mixed prairie range in the central Great Plains. This pasture had historically been subjected to heavier grazing than the one presented in the preceding three-slide example. (This one was on a different research station.) The range shown here had substantially greater relative cover of buffalograss and conspicuously less ralative cover of needle-and-thread and sand dropseed. There was also somewhat greater cover of plains pricklypear though much of this effect was due to greater visibility of the soil surface on the shortgrass form. The most conspicuous difference in species makeup on this shortgrass variant of mixed prairie was absence (or nearly so) of sand sagebrush. Genus Artemisia was instead represented by fringed sagewort (A. frigida).

This shortgrass, sod prairie was "tight land" (more clay) versus somewhat of a "sandy land" range in the previous example that was more of a bunchgrass and sagebrush prairie. Thus differences in species composition and vegetational structure between this example and the one presented immediately above were due to different range sites as well as degrees of use (grazing intensity). Both pastures were grazed by beef cattle.

Major grasses were blue grama, western wheatgrass, buffalograss, and needle-and-thread with relative cover (= % species composition) varying depending on microsite. Overall, blue grama was dominant. Sixweeks fescue and little barley (Hordeum pusillum) were two native annual grasses that were locally common to dominant: Major forbs included wild alfalfa or slim scurfpea (Psoralea tenuifolia), fringed sagewort, western spiderwort, and wavyleaf thistle. Scurfpea was represented by several light-green, bushy plants in the fore- and midgroundbush. Shrubs were limited mostly to plains pricklypear with some soapweed yucca.

A composite "sample" of this range vegetation was presented in the first of these two slides. The second slide featured a shallow drainage (across the foreground narrowing down going to background) dominated by western wheatgrass.

.Central Plains Experiment Station, Washington County, Colorado. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006)

174. Only neophytes and the unappreciative see monotony in mixed prairie (even if it is short)- A shortgrass varaint of the needle-and-thread--blue grama--western wheatgrass cover type on the Central High Plains. These were two more views of the same range subjected to long-term heavy grazing that was introduced in the preceding (immediately above) two-slide set. In spite of the short stature of range plants (partly a consequence of heavy grazing)

The second of these two photographs presented details of the sward of the sodgrass (= shortgrass) community form of mixed prairie. Species in this second 'photo-quadrant" included included blue grama (the circular patch in foreground), buffalograss (yellowish-green "carpet" in left background and right midground), western wheatgrass (most of foreground around circle of blue grama and extending back to buffalograss), pricklypear (center background), and sand dropseed (background behind pricklypear). Western or prairie spiderwort was preent at sparse density and not distinguishable from grass at these distances.

The next (immediately below) two-slide set presented greater detail of composition and structure of the shortgrass component at closer camera range.

Central Plains Experiment Station, Washington County, Colorado. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006)

175. But it can be short- Two successively closer-in views of sward of a predominately shortgrass form of mixed prairie in Central High Plains in this photograph and the one following it. Sward in this photograph was dominated in background by western wheatagrass and by blue grama and buffalograss in foreground. Sand dropseed, needle-and-thread, and sixweeks fescue were present in background along with plains pricklypear.

Central Plains Experiment Station, Washington County, Colorado. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006)

176. Short up close- Plot of sward of the Central High Plains blue grama--western wheatgrass--needle-and-thread mixed prairie described immediately above and presented here at closer camera distance. This photograph showed the relative cover and sod features of the shortgrass component of this mixed-grass (both short-and midgrass species) prairie range. Note the proportion of land surface that was bare ground even in the sodgrass (vs. bunchgrass) form of mixed prairie. This can be compared back to the first (and at greater-camera-distance) photographs of this range vegetation to reveal that the foliar plant cover of even the sodgrass form of mixed praire includes a lot of bare soil surface. This illustrated the potential for soil erosion even with range of this type in proportionately high successional status. This range was in Good to Excellent range condition class even though it had been heavily grazed (fairly high degree of use). Students should not confuse utilization (degree of use; extent of defoliation) with successional status relative to climax (range condition class).

Vegetation in this "photo-quadrant" was dominated by blue grama and buffalograss with a few larger plants of fringed sagewort. Even in the ungrazed state these two co-dominant shortgrass species are never very tall although sexual shoots of blue grama sometimes approach a midgrass height (say, two feet under ideal growth conditions). This was especially the case for this vegetation in early summer before blue grama has much flowering and grain production.

Central Plains Experiment Station, Washington County, Colorado. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006)

177. Closer still, and confusing- Dead sexual shoots (amber-colored with large, full panicles) of sixweeks fescue were still rooted within live and growing shoots of western wheatgrass. At first flush a range examiner unfamilar with this vegetation could be easily confused by "what was what" in this local stand. Sixweeks fescue (like other species bearing the "sixweeks" adjective) is an ephemerial grass, an annual that completes its life cycle extra fast (as short as five to nine weeks perhaps) even by annual standards. Sixweeks fescue is a cool-season annual.

Benefits--hence, evolutionary adaptation--of this pattern of resource allocation on the harsh habitat of the drought-prone, semiarid Great Plains are obvious. A different strategy (Grime, 1979) for adaptation to stress and survival to reproduce in this severe environment was evolved by the cool-season perennial, western wheatgrass. Evolution of different strategies (Grime, 1979) permits these two native range grasses to exploit different resources and conditions so as to occupy different ecological niche even while living side-by-side (and for all rangemen know even to root graft).

These seemingly drab and otherwise unspectacular species provided examples of Darwinian fitness, the degree to which a species, ecotype, or genotype is adapted to its environment so as to leave ecologically optimum numbers and quality of progeny (offspring). This is natural selection or "survival of the fittest", the phenomenon by which those organisms that are best adapted (as determined by their genes or gene action) to their habitat leave the greatest number of competitive offspring (and their genes) to perpetuate their kind (species, ecotype, genotype) in the eternal "struggle for esistence". This is the theory of evolution as first introduced formally by Charles Darwin and Alfred Wallace on 1 July, 1858 and continually refined by generations of biologists. For those with lesser minds (and the Creator whose grand design it is) it is another kind of joy just to revel in the beauty of these species and their own little world.

Central Plains Experiment Station, Washington County, Colorado. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 608 (Wheatgrass-Grama-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13. High Plains- Flat to Rolling Plains Ecoregion, 25d (Chapman et al., 2006)

178. Sixweeks fescue (Festuca octoflora= Vulpia octoflora)- Plants of sixweeks fescue growing on a climax--and heavily grazed--mixed prairie range dominated by needle-and-thread and western wheatgrass in the Central Great Plains. Sixweeks fescue is a native cool-season annual grass that is frequently associated with dominant perennial grasses, especially under disturbance and greater degrees of use.

Sioux County, Nebraska. Late June; hard-dough phenological stage with plants progressing to senescence.

179. Panicles of sixweeks fescue- Two panicles on sixweeks fescue plants that were presented in the preceding two photographs. Sioux County, Nebraska. Late June; hard-dough phenological stage.

181. At its zenith- Two ranges of climax mixed prairie dominated by needle-and-thread and western wheatgrass in Central Great Plains. One range (first of these two photograhs) had been lightly grazed during the current growing season (grazed only in spring). Dominance of the vernal to early estival aspects (societies) by needle-and-thread, in a year of nearly perfect growing conditions for that species, was conspicuous. Other species present in this "mint" condition mixed prairie range included blue grama (the associate species), Junegrass, sixweeks fescue, Sandberg's bluegrass, plains bluegrass (Poa arida), and threadleaf sedge among the graminoids. It reiterated that a wet and cold spring had not been conducive to growth and productivity typical of western wheatgrass so that this co-dominant was underrepresented realtive to needle-and-thread in this photographs (and, as was explained in introduction to this section, other photographs taken during June, 2008). Forbs were very sparse on this Excellent condition class range. The most common forb was fringed sagewort followed by western or prairie spiderwort in number two spot. Other notable forbs included broadbeard beardtongue or broadbeard penstemon (Penstemon angustifolius) and scarlet globemallow.

The other range (second photograph) was also climax (Excellent range condition class) needle-and-thread--western wheatgrass mixed prairie. This pasture was on the other side of a state highway (Nebraska 20) from the range just described. Both pastures were the same range site. Grassland communities on both ranges had--for all intents and purposes was-- the species composition and structure. The only difference was that the first range described had been managed under light grazing whereas the second range was being utilized under heavy grazing. It seemed likely that both grzing intensities had been used in recent grazing seasons. If this was the situation differences in grazing intensity had not resulted in readily observable differences in species composition and range condition class (both pastures were in Excellent range condition class).

In some local areas on both of these ranges--though especially the second--the native annual grass, sixweeks fescue, was the associate species to needle-and-threan and western wheatgrass. This species combination was consistent with the observation that sixweeks fescue increased going into drought on eastern prairies (Weaver, 1954, p. 231) and following drought as the second weed stage of secondary succession on mixed prairie (Weaver and Albertson, 1956, ps. 143, 146).

Key feature of this range type- the physiogonomy of this cover type (ie. the general appearance or overall aspect of this range vegetation) that distinguished it as mixed prairie was dominance by midgrass species (needle-and-thread and western wheatgrass) with some associate species that were of low enough stature at maturity to be interpreted as shortgrasses, at least in these range environments (eg. blue grama, plains bluegrass, sixweeks grama). Blue grama has been interpreted as either a shortgrass species (on habitats where it reaches smaller adult size--including shorter height--and is co-dominant with buffalograss) or a midgrass (on habitats where its sexual shoots grow to heights of, say, two feet or even taller). The relevant physiogonomic feature on this rangeland cover type is that tallgrass species--at least as major components of range vegetation--were not present. The key or distinguishing features that defined this range type as mixed praire were 1) dominance by several species of midgrasses 2) along with shortgrass species and 3) conspicuous absence of tallgrass species. This latter characteristic was in contrast to some other rangeland cover types that were also mixed prairie yet with a prominent tallgrass component (eg. the Wheatgrass-Bluestem-Needlegrass [SRM 606] rangeland cover type covered below). Another key feature of the western wheatgrass--needle-and-thread type was absence of a warm-season dominant. This contrasted with the Wheatgrass-Bluestem-Needlegrass (SRM 606), covered below, and the Wheatgrass-Grama-Needlegrass (SRM 608) that was treated above.

Sioux County, Nebraska. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Western High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2001).

182. Heavy use but not necessarily overuse- Two views of a mixed prairie range with potential natural vegetation co-dominated by needle-and-thread and western wheatgrass. Photographs presented and described in the immediately preceding two-slide set showed this climax vegetation under light grazing (first photograph) and heavy grazing (second photograph). The two photographs of this current caption presented another part of the heavily grazed range introduced immediately above. These two current photographs--the first at longer and the second at shorter or closer camera distance--presented range vegetation at outer perimeter of a sacrifice area (watering facility) where this zone of overgrazing contacted that part of the same pasture that was being heavily grazed but not necessarily being overused, yet alone overgrazed. On this most heavily grazed part of the range that was NOT in the obvious sacrifice area, cover of western wheatgrass was proportionately much greater than cover of needle-and-thread as well as on the range across the road that had been lightly grazed. Cover and density of six weeks fescue was noticeably greater under heavier grazing. Relative species composition of the other range plants was essentially the same.

Did heavier defoliation (degree of use; utilization) adjacent to the sacrifice area constitute overuse? Did it amount to overgrazing resulting from longtern overuse? Obviously there had been a shift between the two climax--two decreaser species--co-dominants. Given that western wheatgrass and needle-and-thread were of the same successional status (climax) a rational case could be made that was no change relevant to range condition class so that this criterion had not changed (ie. the heavy grazed zone outside the sacrifice area was still Excellent range conditin class). Logically this conclusion could be justified as long as needle-and-thread was still present at some realistic density, cover, general abundance, herbage yield, etc.

The morals of this lesson are: 1) there is unavoidably some degree of subjectivity and some room for value judgments, 2) management goals and conclusions are not absolute, 3) conclusions can differ rationally among rangemen, and 4) which is one of the first facts given in the first lecture in Principles of Range Management (typically the introductory course), range management is an art as well as a science.

Sioux County, Nebraska. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Western High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2001).

183. Differences in use- Paired plots of threadleaf sedge (Carex filifolia) under light grazing (first--vertical-- of these photographs) and heavy grazing (second--horizontal-- of these photograaphs). The lightly grazed sedge plant was on the range that presented in the first of two photographs in the two-slide set just before before the immediately preceding two-slide (first photograph above the caption that read "At its zenith"). The heavily grazed threadleaf sedge was on the range shown in the second slide in that first set and in both photographs of the immediatley preceding set. The heavily grazed sedge cn be seen in the right midground of the first photograph of the heavily grazed range.

Sioux County, Nebraska. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Western High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2001).

184. Oppostie sides of the fence- Two views of a fenceline contrast between the mixed prairie range having heavy grazing that was shown above and outside this pasture where there was no livestock grazing (and probably little if any grazing by anything else). The first photograph presented ungrazed mixed prairie to the right and heavily grazed mixed prairie on the left. The second photograph showed ungrazed grassland on the left and heavily grazed mixed prairie to the right.

Sioux County, Nebraska. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Western High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2001).

185. Pocketed disturbance- Local range degradation (range retrogression) caused by plains pocket gopher (Geomys bursarius), a native fossorial (burrowing) rodent. A combination of burrowing and feeding on range forage by the plains pocket gopher was responsible for conversion of a climax needle-and-thread and western wheatgrass mixed prairie in the Central Great Plains into a weed patch, and alien (Eurasian) weeds at that. This gopher-degraded local patch (microhabitat of approximately 30-45 square yards) was on highway right of way (Nebraska 20) in contact with the first of two Excellent condition class ranges presented above having the caption, "At its zenith". Plants of needle-and-thread and western wheatgrass had been killed out and their place was now taken by cheatgrass and tumble mustard.

The first of these two slides showed the climax needle-and-thread--western wheatgrass sward in the background (posterior one-third to a short one-half of photograph) and the weed patch that replaced the Excellent condition vegetation in foreground (front half to two-thirds of photograph). The second slide featured exclusively the weed patch (climax mixed prairie degraded to a local community of Eurasian annual weeds). In this second slide most plants of tumble mustard were in full bloom while cheatgrass was in the soft-dough stage (ie. most plants were at maximum adult size; vegetation at peak standing crop). For whatever reason(s), plants of tumble mustard showed in the first photograph were much less mature (only in prebloom stage) than those in the second slide even though all of these plants where growing within a few feet of each other. Cheatgrass was at same phenological stage (soft-dough) in both of these photographs. Sixweeks fescue, the native annual grass that obviously had greater density and cover on heavier grazed portions of adjoining and proximate mixed prairie ranges (see above), was almost nonexistant on gopher-impacted habitats.

Soil churned up by pocket gophers was visible in both photographs though more so in the second. Such soil moverment was an example of pedoturbation, "mixing within a soil or sediment profile by various processes, such as animal burrowing, tree throw, frreeze-thaw cycles, etc. (Soil Science Society of America, 2001). Pedoturbation is one of many soil forming processes or, perhaps more precisely, one aspect of such a pedogenic process. Vaughan (1972, p. 154) stated that members of the pocket gopher family "are the most highly fossorial North American rodents".

Plains pocket gophers feed on both roots and shoots of range plants. Shoot material is eaten both aboveground as well as pulled from above down into the burrow (Internet Center for Wildlife Camage Management: http://icwdm.org/handbook/rodents/PocketGophers.asp). Also, pocket gopher herbovory includes consumption of and impact on range plants by covering with soil and/or dislodging from the soil. This is the same net result as mechanical cultivation of weeds (ie. smothering so as to prevent photosyntheesis and/or physical removal from soil). In this instance, gophers "cultivated" weeds instead of the climax grass crop. In this context, gophers themselves could be interpreted as "animal weeds" (= a pest or noxious species).

An objective appraisal of this pocket gopher impact would have to allow for the possiblity that disturbance to range vegetation as shown here was beneficial or neutral to the range and not automatically an adverse impact. When viewed in an ecosystem or landscape context and over ecological, especially successional, time scale it is certainly plausible that herbivory (including burrowing) by the native plains pocket gopher played important--perhaps essential--roles in structure and function of the range plant community. Clearly, this species and native range plants co-evolved. It would be naive, if not irresponsible, to assume that there is no natural and well-adapted interaction among them.

It must be underscored that plants which invaded the gopher-disturbed microsite were nonnative species brought onto North America by nonindigenous European man. Thus this zootic disturbance was by definition human- as well as rodent-induced. This local zootic disclimax was partially anthorpogenic in origin (caused to some extent by post-Columbian man). The relevant question would have to be, What would gopher-affected areas be like (what plants would populate the gopher-impacted rangeland) if white man had not carelessly introduced cheatgrass and tumble mustard? Perhaps the native annual sixweeks fescue would have vegetated gopher-denuded spots if Eurasian annual grasses and forbs were not present. Appearance of sixweeks fescue as a member of the second weed stage was described by Weaver and Albertson (1956, ps. 143, 146). Given the small size of gopher-disturbed patches it might be possible that grains of needle-and-thread or rhizomes of western wheatgrass, the dominant decreasers, would quickly repopulate such spots if these climax species did not have to compete with aggressive exotic weeds. It could be speculated as to this or that, but the answer cannot be known without controlled experimentation (ie. gopher-disturbed areas with Eurasian weeds compared to gopher-disturbed areas without these weeds, and with all other variables the same on both of these treatments).

Sioux County, Nebraska. Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-57 (Grama-Needlegrass-Wheatgrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Western High Plains- Sandy and Silty Tablelands Ecosystem, 25g (Chapman et al., 2001).

186. "Mustard and custard"- Three mature plants of tumble mustard at peak blooom (first photograph) and two sexually immature (prebloom stage) plants of tumble mustard (foreground or in front of barb wire in second photograph). Tumble mustard is one of the worst weeds on some western ranges in the vast space from the Great Plains through parts of the Great Basin.

Tumble mustard got its common name from the fact that it is one of several annual forbs that breaks off near the soil surface and blows across the land scattering next year's generation as it "tumbles" with the almost always present wind (Whitson et al., 1992, 237) ). It is also one of several exotic weeds that has this unfortunate (from perspective of the undesirable spread of noxious alien plants) adaptation.

Pat Brady, sidekick to Roy Rodgers, had his share of colorful expressions. "Mustard and custard" was one he employed when things did not quite work out the way they should have. Even without Nelly Belle (Brady's jeep) his words transported the idea that there would be "happier trails" across the range withoug this annual invader and ts especially noxious (aggressively weedy) features like taking soil moisture that could have been used by valuable native forage grasses. Ya reckon Trigger and Buttermilk would take a nip or two off tumble mustard? No, Bullet wouldn't, but you can bet he'd hike his leg on it (off camera of course).

Sioux County, Nebraska. Late June.

187. Alien flowers- Inflorescence of tumble mustard. The cross-resembling arrangement of petals was basis of the traditional family name Cruciferae (crux, meaning cross and ferre, to bear). There are numerous crucifers across the Western Range some of which closely resemble each other (at least to the untrained eye). There are fewer of these "sorta look-alike" mustards in the Central Great Plains where these specimens were photographed.

Sioux County, Nebraska. Late June.

The Wheatgrass-Bluestem-Needlegrass (SRM 606) rangeland cover type is about driest form of Nebraska Sandhills grassland. It is a mixed prairie range type that is a transition between the more xeric wheatgrass mostly Agropyron smithii)-needlegrass (primarily Stipa comata) cover type (SRM 607), that is generally west of the Sandhills, and the mesic bluestem (especially Andropogon hallii)-prairie sandreed (Calamovilfa longifolia) cover type (SRM 602), perhaps the most common rangeland cover type of the Nebraska Sandhills, and that is best developed farther to the east. In this transition range type the dominants were (in relative order) western wheatgrass and needle-and-thread from SRM 607 and sand bluestem from SRM 602.

Key feature of this range type- This form, this range type, of mixed prairie included a dominant tallgrass species. The tallgrass growth form, represented primarily by sand bluestem, was not only a prominent but also a dominant component of this range plant community. This was in contrast to other rangeland cover types of mixed prairie that included only midgrass and shortgrass species such as the Wheatgrass-Needlegrass type ( SRM 607) and the Wheatgrass-Grama-Needlegrass type (SRM 608) covered above. Likewise, sand bluestem also added a dominant warm-season species, a dominant component that was lacking in the western wheatgrass--needle-and-thread type.

Two examples of the Wheatgrass-Bluestem-Needlegrass type (SRM 606) were presented below using two ranges separated by Nebraska Highway 20. Both were degraded to some degree. They were photographed in the first growing season after a prolonged drought (four to five year depending on interpretation of precipitation data). The first range was in high Fair range condition class; the second, in low Good condition. In the late vernal aspect of range vegetation shown invasion by Kentucky bluegrass and the annual bromes (mostly cheatgrass, but also Japanese chess) was conspicuous. Beneath canopy cover of these Eurasian invaders and needle-and-thread there was a relatively dense component of western wheatgrass, the foliar cover of which was atypically sparse due to a late spring (abnormally wet but cold) which resulted in unfavorable growing conditions for this species.

It was still early in the growing season for the warm-season dominant, sand bluestem, so that it had relatively low foliar cover being in earlier stages of phonological development. The same situation obtained for blue grama, the most important warm-season midgrass species. The range plant communities on these two ranges would be considerably different (with a corresponding difference in composition and structure, especially dominance) later in the warm-season phase of plant growth/development (ie. if the estival or autumnal aspects were shown versus the vernal aspect that was presented here).

The co-dominants of these two sample ranges were western wheatgrass and needle-and-thread with the latter having aspect dominance in this spring for reasons described immediately above. Sand bluestem was the obvious associate species. Other principal native species included blue grama, Junegrass, and sand dropseed. Forbs were limited with the most common species being smooth scouring rush or horsetail (Equisteum laevigatum). Widely scattered plants of prickly poppy (Argemone polyanthemos) presented a strinking appearance that far exceeded this species' contribution to plant cover in the range community.

188. Western edge of Nebraska Sandhills- Degraded form (Fair range condition class) of Sandhills mixed prairie of the western wheatgrass-sand bluestem-needle--and--thread type. The range cover type represented by this range is characterized by dominance of the two major cool-season midgrass species of this Central Great Plains region and one of the two major warm-season tallgrass species of this region. In addition to these domiants other major species on this range included the native perennial grass species of blue grama and Junegrass, the naturalized perennial Kentucky bluegrass, and the three annaul grass species of cheatgrass or downy brome, Japanese chess or brome, and sixweeks fescue. There were some plants of threadleaf sedge. The main forb was western ragweed, but it was not common. There were some other forb species, but these weer of little consquence.

Cherry County, Nebraska Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-60 (Wheatgrass-Bluestem-Needlegrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Nebraska Sand Hills- Sand Hills Ecoregion, 44a (Chapman et al., 2001).

189. Not the best; not the worst- Sward of the western wheatgrass-sand bluestem-needle--and--thread Sandhills mixed prairie range (Fair range condition class) presented in the immediately preceding slide. Species present in this "photo-quadrant" included western wheatgrass, needle-and-thread, blue grama, Junegrass, Kentucky bluegrass, downy brome or cheatgrass, Japanese chess or Japanese brome, and western ragweed.

Cherry County, Nebraska Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-60 (Wheatgrass-Bluestem-Needlegrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Nebraska Sand Hills- Sand Hills Ecoregion, 44a (Chapman et al., 2001).

190. Not perfect, but better- Example of Nebraska Sandhills mixed prairie of the western wheatgrass-sand bluestem-needle--and--thread range type. These two land-sweeping photographs presented physiogonomy and strucure of this grassland at a stage approaching climax stage (Good range condition class). The range presented hee was on the opposite side of Nebraska Highway 20 straight across from the Fair condition range described in the two immediately preceding photographs. This range had considerably greater species diversity than the Fair condition range. Cover of sand bluestem, the only tallgrass species with much cover or density (little bluestem was represented by a few, widely scattered individuals) was conspicuously greater than on the Fair condition range. (Sand bluestem was prominent in center foreground of both photographs, especially the second one.) Likewise, cover and density of needle-and-thread and Junegrass were considerably greater on the Good condition class range, but general and relative abundances of western wheatgrass and blue grama were about the same on both pastures. There was very little cover of Kentucky bluegrass, an alien though naturalized invader, on this Good condition range. There was much less cover of the naturalized exotic bromes on the Good condition range, but general abundance of sixweeks fescue was about the same on both of these pastures.

This Good condition range had more forbs but less forb cover than the Fair condition range. The major range forb on this Good pasture was common horsetail (Equisteum arvense). Western ragweed was the second most common forb, but it had less cover than on the Fair condition range. Prickly poppy (Argemone polyanthemos) was more common on the higher condition class range, but this biennial was far from common.

Details of the sward of this Good condition range was presented in the next photograph.

Cherry County, Nebraska Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-60 (Wheatgrass-Bluestem-Needlegrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Nebraska Sand Hills- Sand Hills Ecoregion, 44a (Chapman et al., 2001).

191. More like it- Sward of Nebraska Sandhills mixed prairie of the western wheatgrass-sand bluestem-needle--and--thread range type. This was a "photo-plot" of the Good condition class range featured in the two immediately preceding photographs. Sand bluestem (the largest, tallest grass in center foreground) was conspicuous. Needle-and-thread, one of the regional cool-season dominants, was the most abundant species in the sample of range vegetation presented here. Other species visible in this slide included western wheatgrass, blue grama, cheatgrass (very limited) and the two forbs, common horsetail and western ragweed.

Cherry County, Nebraska Late June (early estival aspect). FRES No. 38 (Plains Grassland Ecosystem). K-60 (Wheatgrass-Bluestem-Needlegrass). SRM 607 (Wheatgrass-Needlegrass). Closest description in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Plains Grassland 142.1, Mixed "Short-Grass" Series 142.13, but this missed more than hit it. Nebraska Sand Hills- Sand Hills Ecoregion, 44a (Chapman et al., 2001).

192. Mark of a good sandhills steward- Sandhills in the Great Plains are one of the wind-sensitive of all range ecosystems in North America. The beauty and productivity of these marvelous grassland ranges belies their fragility to wind-caused soil erosion. A commonsense and ideal practice to prevent wind erosion on ranges in the Nebraska Sandhills is the lashing together of discarded automotive tires (often with the universal standby of used baling wire) around utility poles within cattle-rubbing distance. Range animals, especially bovids like cattle and buffalo, love to rub on poles and tree trunks (both of which are scarce on this rangeland). This rubbing or bovine form of scratching is more common in spring when animals are shedding their winter coats or when they are heavily infested with lice. The though yet vulnerable range plants would be trampled out around posts, power poles, cottonwood snags, etc. where animals habitually rub. Loss of plant cover causes a "break" in the sward and a resulting "opening" on the land awaiting soil removal by eolian forces.

Some faithful stewards like power company linesmen responsible for this power corridor or the owner of this range took the appropriate preventive action to protect this valuable yet sensitive grazing land from what could quickly become severe wind erosion. A well-earned tip of the hat to the hard workers who did their part in the wise use management of this grassland.

Cherry County, Nebraska Late June (early estival aspect).

Foothills Bluegrass Mixed Prairie: an ambiguous range type- Developing in the foothills of the Sourhern Rocky Mountains (Laramie Mountains) and situated at margins of needle & thread-blue grama-western wheatgrass mixed prairie (Kuchler 57), blue grama-buffalograss mixed prairie (Kuchler 58), and ponderosa pine-Douglas-fir montane forest (Kuchler 17) are relatively small, isolated grasslands of mid-height grasses, especially the larger species most notably Canby's bluegrass (Poa canbyi) and big bluegrass (P. ampla). Presented in this section was an example of these foothill grasslands some of which were dominated by larger bluegrasses and that appeared as a form of mixed prairie. These granitic (generally igneous parent material)-based range sites (Igneous and Shallow Igneous, Foothills and Mountains Southeast) were described by the Natural Resources Conservation Service (1998) as having bluebunch wheatgrass (Agropyron spicatum) as the most abundant, if not the dominant, range plant species. Percent composition of bluebunch wheatgrass was shown for different soil series (Natural Resources Conservation Service, 1998, ps. 280-309 passim) at values from 35% down to 15%. Slimstem muhly (Muhlenbergia filiculmis) and threetip sagebrush (Artemisia tripartita= A. trifida) were listed as major species of the potential plant community (Natural Resources Conservation Service, 1998). There was no reference to Canby's or big bluegrass, period.

This description differed drastically from the units of potential natural vegetation mapped and described by Kuchler (1964, 1966) as given in the preceding paragraph (see especially Kuchler, 1964, units 64 and 66). Mapping and describing a bluebunch wheatgrass-dominated grassland (more like an eastern island of the Palouse Prairie) was also inconsistent with Society for Range Management (SRM) rangeland types described in Shiflet (1994), specifically SRM 606, 607, 609 that represented range vegetation on this region. Instead the NRCS (1998) categorizations were essentially those of SRM rangeland cover types (SRM 302, 303, 304, or some combinations thereof) given for the Northern Rocky Mountains province (Shiflet, 1994, ps. 27-29). This was true in particular with regard to range plant species dominating deteriorated ranges described as dominated by bluebunch wheatgrass.

The range vegetation shown and described in this section (a Rogert-Rock outcrop; Shallow Igneous range site) did not fit the range plant community descriptions of the Natural Resources Conservation Service (1998), for either climax or stages of range degradation. Nor did ecological site descriptions (Natural Resources Conservation Service, 2006) match this vegetation. Neither did this bluegrass-dominated e featured range plant communities described in published rangeland cover types (Shiflet, 1994). Rather, this range vegetation was dominated overwhelmingly by various bluegrassees, especially Canby's bluegrass (P. canbyi), the dominant species, and the similar big bluegrass (P. ampla). Grass species from other conterminous mixed prairie types (notably blue grama;, to lesser extent, western wheatgrass; and with less cover yet, needle-and-thread, for example) were present but quite limited. Other bluegrass species included (and in relative order based on general abundance, cover, etc.) Sandberg bluegrass (P. secunda), nodding bluegrass (P. reflexa), and-though restricted to small and more mesic depression-a Poa species with an immature panicle that suggested--but could not be positively identified as-- fowl bluegrass (P. palustris). Mutton bluegerass (Poa fendleriana) was present growing on an adjacent area, but was not found on the range that was photographed and presented here.

Almost all green grass plants were Poa species with mature (or nearly so) spikelets. The range vegetation presented here was composed in overwhelmingly quantity (based on general cover, density, aspect abundance) of bluegrasses, especially Canby bluegrass, the single dominant species. Again, blue grama, western wheatgrass, and needle-thread (the zonal climax dominants) were present, but ranking well behind Canby, big, and Sandberg bluegrasses. Junegrass was present at relative abundance approaching that of trace quantity. Also present at edges of the gravely environment of this foothill bluegrass range was sheep fescue (Festuca ovina var. rybergii) and a trace of what appeared to be King's spikefescue (Leucopoa kingii). Also present (and at typically high densities) were threetip sagebrush (A. tripartita subsp. rupicola) and fringed sagewort (Artemisia frigida) as well as the conspicuous forbs, miner's candle (Cryptantha virgata= Oreocarya virgata) of the Boraganaceae and tufted fleabane (Erigerion caespitosus). Another common forb on this range was the umbel, whidkbroom parsley (Harbouria trachypleura).

The range site descriptions provided in the Soil Survey for the Albany County, Wyoming area (Natural Resources Conservation Service, 1998) simply put were not appropriate for--they did not fit--this range vegetation in any successional stage. Ecological site descriptions (Natural Resources Conservation Service, 2006) did not even list Canby's bluegrass. It was possible that Sandberg's bluegrass was used as a generic name that included Canby's and big bluegrasses. The NRCS Plant Guide for Sandberg bluegrass interpreted this as a Sandberg bluegrass complex that included big bluegrass, Canby's bluegrass, and several recognized Poa species. This was consistent with the treatment in Barkworth et al. (2007, ps. 586-688) wherein the former P. canbyi was reintepreted as a "smooth, larger" ecotype of P. secunda subsp. secunda. The continent-wide treatment by Barkworth et al. (2997) contrasted with the manual for Wyoming (Skinner et al., 1999, ps. 78-82) in which the species P. canbyi was retained and distinguished clearly from P. secunda subsp. secunda. Mr. Bob Mountain, U.S. Forest Service, explained (personal communication) to this author that throughout this plains and mountains complex of range types and sites there were many Poa species yet Forest Service range workers on the Medicine Bow National Forest, which neighbored with the range described below, generally tried to distinguish among these species. For example, in doing range vegetation inventories Forest Service rangemen listed separately, to the extent practicable, such species as P. canbyi, P. ampla, P. fendleriana, P. secunda (= P. sandbergii), P. nervosa, P. palustris, and P. reflexa. Lumping several bluegrass species under a generic Sandberg's bluegrass --if indeed such was the case for Natural Resources Conservation Service (1998, 2006) range site descriptions--could be overly simplistic and lead to extreme confusion. Even if Canby's bluegrass is an ecotype of P. secunda subsp. secunda it is different from the ecotype of P. secunda subsp. secunda that is Sandberg's bluegrass. Both of these species, forms, ecotypes, etc. were present on the rangeland shown and presented below. If Sandberg's bluegrass is is an obvious increaser on this range site, it is still possible (erhaps even highly probable) that the larger species, ecotypes, or whatever like Canby's and big bluegrass are likely to be decreasers.

Whatever the explanation, neither climax or any of the published states of range retrogression (Natural Resources Conservation Service, 1998, p. 113; Natural Resources Conservation Service, 2006) described, at least not adequately, the foothills bluegrass mixed prairie that was shown and described in the following section.

Contrary to published range site descriptions and rangeland productivity tables (Natural Resources Conservation Service, 1998) the bluegrass-foothills grassland was not an island of the Palouse Prairie. Nor again (as explained above) was this range vegetation, which was most likely at some higher successional state (at least subclimax) covered in any of the Kuchler (1964, 1966) units of potential natural vegetation or in rangeland cover types (Shiflet, 1994). In fact, the most telling evidence that something was wrong or incomplete in published descriptions of this climax.or potential natural vegetation was the glaring contraction between Kuchler (1964, 1966) and Natural Resources Conservation Service (1998) designations. The Natural Resources Conservation Service (1998, p. 113) described this range vegetation as, in effect, an eastern extension of Palouse Prairie (bluebunch wheatgrass-dominated with various other wheatgrasses and Idaho dfescue) whereas Kuchler (1964, 1966) mapped it as shortgrass mixed prairie (grama-buffalograss). by were in extreme conflict. In the Kuchler (1966) map version provided in Garrison et al. (1977) this potential natural vegetation was mapped as unit 58 (Grama-Buffalograss; Bouteloua-Buchloe), but based on the Natural Resources Conservation Service (1998) range site description it would be Kuchler (1966) unit 43 (Fescue-Wheatgrass; Festuca-Agropyron) or unit 44 (Wheatgrass-Bluegrass; Agropyron-Poa). Obviously this was an extreme conflict where both cannot be correct. In this author's view, neither was correct.

Prof. J. Daniel Rodgers, University of Wyoming, explained to this author (personal communiction) that Canby's bluegrass was a common dominant species, especially above the foothills and up to the pine forests, along the Rocky Mountain Front Range and neighboring areas. Caby's bluegrass is especially common and dominant on gravelly, granitic soils such as those derived from Sherman granite. On such range sites Canby's bluegrass is frequently to typically associated with threetip sagebrush. Dr. Rodgers further explained that, as of that time, there was not a published, readily available description of range vegetation for this area. In essence there is not a published description of the foothill bluegrass or Canby bluegrass range type, at least there is not a readily accessible description at time of this writing.

Irrespective of whether Canby's bluegrass is a distinct species or an ecotype of Sandberg's bluegrass or is a decreaser or an increaser, and thus the foothills bluegrass mixed prairie be climax (potential natural) vegetation or a higher seral stage, the indisputable fact remained that the Canby bluegrass-threetip sagebrush range plant community described below was representative of typical ranges throughout this area.

Photographs were taken in early summer (late June) following an abnormal year (an unusually moist to wet yet cold spring. In this general locality grasses like western wheatgrass and bluebunch wheatgrass took several weeks longer to reach advanced phenological stages. In fact, western wheatgrass generally did not advance to maturity as in typical years. Hence, the photographed range vegetation was atypical with some species such as bluebunch wheatgrass under-represented (if present it was in earlier stages of phenology). That noted, it was emphasized that this photographer did not observe bluebunch wheatgrass even at earlier stages of growth. If this species was present--as seemed plausable given its documented occurrence in this area (Skinner et al., 1999, p. 155)-- it was as a minor component based on cover, density, and general abundance. Even western wheatgrass growing on this range was more common on low-lying, more mesic microsites (see below) than on other local habitats of this gravelly, shallow edaphic environment.

Relatively high cover of threetip sagebrush and fringed sagewort in the range plant community presented below was consistent with brief range site descriptions by the Natural Resource Conservation Service (1998). Occurrence of fringed sagewort fit descriptions of all the above cited SRM rangeland cover types (SRM 302, 303, 304, 606, 607, 609) so as to be of limited value for distinguishing among several range types including those of contiguous cover types. Rather it was presence of threetip sagebrush that was of telling importance for this range type.

This range vegetation was clearly dominated by Canby bluegrass with others like big and Sandberg's bluegrass as associate species. Given the conditions and general situation described above it seemed likely that the range vegetation featured here was in some stage of retrogression. The extent of range deteioration (departure ferom whatever the climax was) could not be determined though it likely was not lower on the sere than subclimax. As stressed above, these species were not listed as being component species in any of the published range site or rangeland cover type descriptions in any state of range degradation. Thorough description of range sites and types would require inclusion of large species of native bluegrasses which made up most of the range vegetation at a stage in development of the natural plant community.

This foothill mixed prairie vegetation was featured immediately below. It was presented because it was it is a widespread range plant community in what appeared as a broad ecotone between Great Plains grassland and Rocky Mountains forests, scrublands, and parks. Detailed discussion, including that of the relevant literature, was provided to point out emphatically that this range vegetation was not described in readily available material (if at all) and certainly not to the extent of most other units of range vegetation. Furthermore, much of the existing descriptions are contradictory, conflicting, and confusing. This was due to such things as inconsistency among authorities and ambiguity in plant names. Hopefully somebody will recognize this glaring omission and write descriptions of this and associated rangeland cover types as well as more precise reports of range sites.

193. Foothills range in the Laramie Range- Canby's (Canby) bluegrass-dominated mixed prairie with Wyoming threetip sagebrush (Artemisia tripartita subsp. rupicola = A. trifida) the associate plant species on the Front Range of the Rocky Mountains. Other important range plants included blue grama, Sandberg bluegrass (readily distinguishable from other bluegrasses by smaller size and more advanced maturity or phenological development); fringed or plains sagewort (A. frigida); and small, isolated colonies of western wheatgrass in local depressions. Junegrass was present as sparsely scattered individuals. There were also some scattered plants of what appeared to be big bluegrass (Poa ampla). These plants were partly distinguishable from P. canbyi by their wider leaf blades, but identification was not completely positive because plants that were thought to be big bluegrass had not yet produced panicles. There were some plants that may have been King's spikefescue (Leucopoa kingii), but these were not in flower and could not be identified either. There were a few forb species present including tufted fleabane (Erigeron caespitosus), whiskbroom parsley (Harbouria trachypleura), and miner's candle (Cryptantha virgata= Oreocarya virgata). Individual plants of these species were conspicuous in a "sea of grass shoots", but none of them contributed substantial cover (relative or absolute) or were of notable density or herbage production.

Needle-and-thread, which was the "super-abundant"dominant of other rangeland cover types in the mixed prairie of adjoining and lower elevation landscapes, was "conspicuous by its absence" in the foothill range vegetation described in this section. Likewise, bluebunch wheatgrass, reportedly the climax dominant of this range site, appeared to be absent ("totally missing") from this range. Unusually cold and wet conditions in late winter throughout spring could have delayed development of any bluebunch wheatgrass that was present, but this worker did not observe any plant material--either dead, decaying tissue from the preceding year (eg. naked spikes, weathered leaves or culms) or young, energing shoots of the current year--that evenly faintly resembled this species. Likewise, this observer did not notice any slimstem muhly, the other reported (Natural Rsesouces Conservation Service, 1998) major decreaser grass for this range site. Slimstem muhly is especially well-adapted to shallow granitic soils (Skinner et al., 1999, p. 202) like those on this range. It was hihgly likely that both bluebunch wheatgrass and slimstem muhly were on this range at trace to slight amounts and that past overgrazing had eliminated both of these perennial decreasers. Since earliest days of occupation by whiteman this area was heavily grazed by livestock--as beasts of transport for all sorts of travelers and commerical ventures (including the first transcontentintal railroad) as well as commodities produced by sheepmen and cattlemen, alike.

The unique geologic features on this rangeland combined with the "ambiguous" range plant community as detailed above resulted in an intriguing and unusually romatic "rangescape" The geologic formation featured here was the Sherman Mountains (composed of Sherman Granite), remnants of the Sherman batholith, in the larger Laramie Range (Laramie Uplift). The Laramie Range is one of two prongs or forks of the Front Range in this area, the Medicine Bow Range being the other prong. Both of these geologic prongs or forks are in turn part of the eastern slope (the front edge) of the Rocky Mountains known as the Front Range (Lageson and Spearing, 1988, ps. 23-26; Edwards and Frost, 2000). The mountain building, the process of orogeny, by which the Rocky Mountains were formed takes its name from the Laramie Range: Laramide Orogeny. This geologic event took place during the Late Creatceous Epoch rougly 80 to 70 million up to 55 to 35 million years before present. Northern and southern portions of Laramie Range are comprised of two kinds or forms of bedrock. The bedrock of the southern part (the parent material of soils in this area) is Sherman Granite formed in the Late Precambrian Geologic Time and that crystalized to its present state about 1.4 billion years before present during the early Mesoproterozoic Geologic Eon (Lageson and Spearing, 1988, ps. 25-26; Edwards and Frost, 2000).

The landscape shown here was on the so-called Gangplank, a large alluvian fan out of the Laramie Range which, being an uplifted gradual slope, served as an easier overland route (including for the transcontentintal railroaad) across this northern part of the Front Range. Use as a trade route unavoidably resulted in heavy grazing by livestock which could have resulted in range degradation and replacement of species like bluebunch wheatgrass and slimstem muhly by species like Cnby's bluegrass and blue grama. In current times knowledgable local folks make reference to bluegrass, blue grama, and "short sagebrush" but not to other species. Whatever was or might be, this widespread range vegetation was clearly 1) bluegrass-dominated mixed prairie that was 2) not included in readily accessible descriptions of range types and range sites.

Albany County, Wyoming. Late June; late vernal to early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). Range site: Shallow Igneous, 15-19 inch precipitation, Foothills and Mountains Southeast (Natural Resources Conservation Service, 1998, 2006). Southern Rockies- Foothill Shrublands Ecoregion, 21d ( Chapman et al., 2003).

194. Sherman Mountains mixed prairie- On the "rangescape" of the Sherman Mountains a bluegrass-dominated mixed prairie of bunchgrass form (phusiogonomy) had developed (perhaps it had retrogressed from a higher successional stage). Canby bluegrass was the overwhelming dominant (based on cover--both foliar and basal--as well as density and, especially, biomass) with Wyoming threetip sagebrush the associate species. The other major (common) range species were blue grama, Sandberg's bluegrass, western wheatgrass (limited to local depressions), fringed or plains sagewort, Junegrass, and big bluegrass. The latter two species were present as individual plants or in small, isolated patches. Big bluegrass was tentatively distinguished from plants of Canby's bluegrass that was at peak inflorescence (grain in hard-dough stage). Plants that were thought to be big bluegrass had conspicuously wider leaves and a deeper-green color than Canby's bluegrass. Sandberg's bluegrass had already fully matured and was entering dormancy. Forbs were incidental and included tufted fleabane, whiskbroom parsley, and miner's candle.

Needle-and-thread, the regional dominant of Central Great Plains grasslands (and extremely abundant in this year), was absent--completely missing--from this range type. Such was also the case for bluebunch wheatgrass, the reported (Natural Resources Conservation Service, 1998, 2006)) climax, decreaser, dominant for this range site. This observer doubted that either of these grasses was a major species on the shallow, droughty soil of this fairly widespread range type. Slimstem muhly was the other dominant decreaser grass on this range site according to descriptions by the Natural Resources Conservation Service (1998, 2006) and this species also was not a major component of the range plant community on this range. Overgrazing as far back as the frontier era may have contributed to elimination of these two designated decreasers from this range. Local grass-growing conditions preceding these photographs of current-season vegetative growth was another partial explanation for the obvious species composition of this range plant community. An ususually cold and wet spring had hampered development of late-season species like bluebunch wheatgrass throughout the Laramie Range prior to time of these photographs (Mr. Bob Mountain, M edicine Bow National Forest, personal communication). This situation could not have explained absence of previous year's plant material of bluebunch wheatgrss or slimstem muhly that should have been present if these species grew on this range. Lack of such herbaceous reside (at least in any meaningful amounts) substantiated absence of these species in the vegetation of this range.

The rock outcrops of smaller boulders on this range were of Sherman Granite, a coarse-grained igneous rock of the early Mesoproterozoic Geologic Eon (about 1.4 billion years before present), that make up much of the Sherman Batholith. A batholith is a large geologic mass of igneous intrusive (plutonic) rock derived from magma that cools and ascends to the land surface. Frost et al.(2000) concluded that the Sherman Batholith was most likely caused by partial melting of rocks derived from Earth's mantle.

Albany County, Wyoming. Late June; late vernal to early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). Range site: Shallow Igneous, 15-19 inch precipitation, Foothills and Mountains Southeast (Natural Resources Conservation Service, 1998, 2006). Southern Rockies- Foothill Shrublands Ecoregion, 21d ( Chapman et al., 2003).

195. Physiogonomy and structure of foothill mixed prairie- A bunchgrass form of mixed prairie dominated by Canby's bluegrass (with Wyoming threetip sagebrush as associate) on the Sherman Mountains of the Laramie Range. This "photo-plot" was taken at camera focal length to feature the physiogonomy and architecture (structure as to layers of vegetation). Other abundant (based on apparent density, cover, and standing crop) plant species included blue grama, western wheatgrass (localized dense colonies limited to small depressions), Sandberg bluegrass, fringed or plains sagewort, Junegrass, and big bluegrass. Forbs were incidental (at least in the spring society) though conspicuous. These included tufted fleabane, miner's candle, and whiskbroom parsley.

This range plant community was that of late spring-early summer in a year of atypically wet and cold conditions commencing in late winter. Mr. Bob Mountain, Medicine Bow National Forest, explained to this author (personal commjnication) that weather conditions earlier in the plant-growing season had delayed development of range plants, especially at higher elevations. This was particularily pronounced in certain species of grasses including bluebunch wheatgrass. It was plausible that bluebunch wheatgrass and slimstem muhly, the two species listed as decreaser dominants in descriptions of this (and similar) range sites (Natural Resources Conservation Service, 1998, 2006), had much lower cover and biomaass in this area so as to be under-represented in this range vegetation. That would not, however, explain the lack of dead and weathered plant material of bluebunch wheatgrass and slimstem muhly that would have persisted from the previous year if these two species grew on this range. The only logical concluisions were that 1) this range was in some state of departure from a bluebunch wheatgrass-dominated climax or 2) bluebunch wheatgrass is not the potential dominant of this range site represented by the existing vegetation.

The range plant community shown here was that of the later vernal society. If other major species such as bluebunch wheatgrass were present on this range--and this rangeman certainly did not find them--they would have formed a later-season society (ie. they would not likely have been at sexually reproductive stages at this point even in a year of more typical rowing conditions). Grassland dominated by bluegrass (especially Canby's and big bluegrass) and "short sagebrush" was the range vegetation that local people in the coffee shops described for this locality to the aurthor. That was the range plant community presented in this slide.

Sherman Granite, a distinctive coarse-grained hornblende granite, comprises a major part of the Sherman batholith of the Laramie Range. Gravel derived in large part from Sherman Granite can cover up to approximately half of the surface of certain soils such as on the Rogert-rock Outcrop unit of this rangeland (Natural Resources Conservtion Service, 1998). This gravel was visible on the land surface in this photograph as well as several other slides of this range vegetation presented below. Composition of Sherman Granite was provided by Edwards and Frost (2000) and Frost et al. (2000).

Albany County, Wyoming. Late June; late vernal to early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). Range site: Shallow Igneous, 15-19 inch precipitation, Foothills and Mountains Southeast (Natural Resources Conservation Service, 1998, 2006). Southern Rockies- Foothill Shrublands Ecoregion, 21d ( Chapman et al., 2003).

196. Species composition of a foothill mixed prairie- Canby's bluegrass-dominated a bluegrass mixed prairie at edge of the Front Range and Central Great Plains. Wyoming threetip sagebrush was the associate species. Other important range plants included Wyoming threetip sagebrush, blue grama, western wheatgrass (in slight depressions that afforded a more mesic microhabitat), Sandberg bluegrass, fringed or plains sagewort, and big bluegrass. The latter was tentatively identified only, because plants that appeared to be big bluegrass had not yet produced inflorescences and this author being "a stranger to these parts" could not identify them from vegetative characteristics. A wider leaf and deeper green-color separated them from plants of Canby's bluegrass, this latter of which was unquestionably identified from spikelet features (shown below).

Successional status of this range vegetation was not known. The range site description (Natural Resources Conservation Service, 1998; 2006) described the climax vegetation as being dominated by bluebunch wheatgrass slimstem muhly, and threetip sagebrush with Sandberg bluegrass and threestem sagebrush increasing under range retrogression. This author did not find any bluebunch wheatgrass on this range, but it had been a belated spring with cold,wet conditions from late winter until the present early summer so that some species like bluebunch wheatgrass were "far behind schedule" while residual herbage was highly weathered making identification of dead plant material difficult to impossible for all but local folks familar with the species at all stages of phenology and decomposition. It was also possible that Canby's bluegrass comprises most of the vernal society of this mixead prairie and later-maturing species would make up estival or autumnal societies. Nonetheless, Canby's bluegrass was dominant, even based on examination of decayed-weathered herbage. Bluebunch wheatgrass was a minor component of this range plant community at best.

The question with regard to successional state--hence, range condition class--of this range vegetation hinged on the grazong response of Canby's bluegrass. If it is an increaser like Sandberg's bluegrass this range was at substantial departure from climax (probably in Fair range condition class). If, on the other hand, Canby's bluegrass is a natural dominant (decreaser) this range plant community would rate substantially higher, perhaps being at subclimax stage. Wyoming threetip sagebrush is an increaser and its presence at high levels of abundance (relative cover) strongly suggested some degree of range degradation, again possibly Fair to low Good condition class.

Regardless of the ecological condition of this range it was representative of much of the rangeland in this area, and was presented as such.

Albany County, Wyoming. Late June; late vernal to early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). Range site: Shallow Igneous, 15-19 inch precipitation, Foothills and Mountains Southeast (Natural Resources Conservation Service, 1998, 2006). Southern Rockies- Foothill Shrublands Ecoregion, 21d ( Chapman et al., 2003).

197. Stand of Canby's bluegrass- Local "photo-sample" of the population of Canby's bluegrass that dominated a bunchgrass mixed prairie in the foothills of the Laramie Range. Wyoming threetip sagebrush was the associate range plant on this rangeland.

Sherman Granite, especially conspicuous in this photograph, was the primary parent material of this soil (Rogert-Rock Outcrop). Readers wishing more details regarding Sherman Granite were referred to the report by Frost et al. (1999).

Albany County, Wyoming. Late June; late vernal to early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). Range site: Shallow Igneous, 15-19 inch precipitation, Foothills and Mountains Southeast (Natural Resources Conservation Service, 1998, 2006). Southern Rockies- Foothill Shrublands Ecoregion, 21d ( Chapman et al., 2003).

198. Laramie Range mixed prairie- A bunchgrass form of mixed prairie dominated by Canby's bluegrass and Wyoming threetip sagebrush had developed on s shallow soil (Rogert-Rock Outcrop) adorned by large rocks (small boulders) of Sherman Granite. Sandberg's bluegrass was the secon most abundant grass. It was readily distinguished from Canby's bluegrass by smaller size and phenological stage approaching senescence. Tufted fleabane and miner's candle were two forb species present in the "photo-quadrants" shown here. There were also some plants of fringed or plains sagewort. Sherman Granite provides a harsh habitat for various speecies of lichen that decorate the already colorful rocks of this range type. Lichen are part of the range vegetation even though this mutualistic relationship between fungus and algae does not constitute a vascular plant.

General absence of shortgrass species other than the notable blue grama denoted this as a midgrass mixed prairie. This grassland had the physiogonomy, general height, and a species composition with an obvious affinity of regional Great Plains grassland such that this was mixed prairie. It was not, however, mixed prairie in the structural feature of having prominent layers of shortgrass and/or tallgrass species along with that of the midgrass.

Albany County, Wyoming. Late June; late vernal to early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). Range site: Shallow Igneous, 15-19 inch precipitation, Foothills and Mountains Southeast (Natural Resources Conservation Service, 1998, 2006). Southern Rockies- Foothill Shrublands Ecoregion, 21d ( Chapman et al., 2003).

199. Mixed prairie at the farthest reaches of its domain- Sward of a mixed prairie of the predominant bunchgrass form at the extreme western margin of the Great Plains just below the foothills of the Front Range. This local species-rich stand was dominated by Canby's bluegrass "assisted" with an array of other rmajor grasses including big bluegrass, Sandberg's bluegrass, sheep fescue, sixweek's fescue, western wheatgrass, and blue grama.. Cheatgrass or downy brome and crested wheatgrass were minor grass species, but their presence was evidence of the naturalization of these two introduced Eurasian species. There were no forbs or shrubs in this range plant community.

This range vegetation was lower in elevation though in close proximity to the foothill form of mixed prairie dominated by Canby's bluegrass and Wyoming threetip sagebrush described immediately above. The range environment of this exclusively grass-comprised plant community with deeper, more mesic soil was much less harsh than that of the bluegrass-threetip sagebrush community on the foothill range in the Sherman Mountains. Dominance of both range plant communities by Canby's bluegrass and presence of other grass species "shared in common" was evidence of the vegetational affinity of these two forms of midgrass mixed prairie.

Laramie County, Wyoming. Late June; early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). High Plains- Moderate Relief Plains Ecoregion, 25c ( Chapman et al., 2003).

200. Cool-season mixed prairie- At the western boundary of the Great Plains just below the foothills of the Front Range a mixed prairie had developed that was made up almost exclusively of cool-season grasses. Sheep fescue (Festuca ovina var. rydbergii or, perhaps, F. brachyphylla subsp. saximontana=F. saximontana= F. brachyphylla) was the overwhelming dominant, but Canby's bluegrass, Sandberg's bluegrass, and western wheatgrass were also well-represented in this local stand from which forbs and shrubs were absent. Also more or less absent were naturalized introduced species like cheatgrass and crested wheatgrass. This range vegetation--the range ecosystem generally--had a remarkable rate of herbage (biomass) productivity, but species richness was noticably less than of most other range plant communities in this general area.

This was a more mesic form of mixed prairie than the mixed prairie at higher elevtions in the foothills of the Front Range to which a close affinity obviously existed in both close proximity and the commonality of Canby's bluegrass. This was predominately a midgrass mixed prairie with no tallgrass species while the shortgrass element was limited to such species as Sandberg's bluegrass and blue grama, of which no plants representing these two species were in this local stand.

Laramie County, Wyoming. Late June; early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). High Plains- Moderate Relief Plains Ecoregion, 25c ( Chapman et al., 2003).

201. Standing tall- Local stand of foothills mixed prairie consisting of Canby's bluegrass (overall dominant), sheep fescue, and western wheatgrass. The lattter of these species was abnormally under-developed for this time of year due to a prolongued cold yet wet late winter through to present. An example of a stunted western wheatgrass plant was in lower left corner. On much of the habitat of this foothills form of mixed prairie western wheatgrass forms plants that are much smaller than typical and which appear almost cespitose in spite of the usual creeping rhizomes of this species. These upland, often gravelly, environments are marginal for this more mesic of the major midgrasses.

Festucoid grasses clearly predominate at latitudes this far north.

Laramie County, Wyoming. Late June; early estival aspect. FRES No. 38 (Plains Grassland Ecosystem). No appropriate units given in Kuchler (1964, 1966) or Society for Range Management (Shiflet, 1994). High Plains- Moderate Relief Plains Ecoregion, 25c ( Chapman et al., 2003).

202. Canby's bluegrass (Poa canbyi)- The taxon represented by these specimens is either distinct species (Poa canbyi) or a larger-growing ecotype of P. secunda subsp. secunda.The latter interpretation was used in the official, authoritative Flora of North America (Barkworth, 2007, ps. 586-588) whereas recognition of P. canbyi is the traditional treatment that was still used in Grasses of Wyoming, the state grass manual, (Skinner et al., 1999, p.78-81, 82) and, which according to Hitchcock and Chase (1951, p. 938), traced back to 1906.

On initial sighting of this plant on the range one's first impression is something like , "Schzam! Sandberg's bluegrass grown under irrigation, fertilization, and on auxins". In other words, individuals of this taxon appear as "giant Sandberg's bluegrass" or "Sandberg's bluegrass except its too big". Canby bluegrass reaches heights roughly twice those of Sandberg bluegrass (Skinner et al., 1999, ps. 78, 97). Whatever the most precise name and taxonomic interpretation, Canby's bluegrass is both widespread in the northern Front Range and different morphologically from anything else. The larger size of Canby's bluegrass led to selection and release by the Soil Conservation Service Plant Materials Center and Washington and Idaho Agricultural Experiment Stations of the cultivar, Canbar.

Albany County, Wyoming. Late June; grain in hard-dough stage.

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203. Panicle of Canby's bluegrass- Panicles of Canby's bluegrass vary from narrow to relatively wide and from compact to open (Hitchcock and Chase, 1951, p. 134; Skinner et al., 1999, p. 81). They are generally heavy grain-bearing inflorescences. These examples were typical, at least the most commonly morphological form in those found growing on this range.

Albany County, Wyoming. Late June; grain in hard-dough stage.

204. Spikelets of Canby's bluegrass- Two closer-in views of parts of Canby's bluegrass panicles showing greater detail of spikelets. Areas of darker coloration (pigmentation) on glumes and, especially, lemmas and paleas is a common feature of this species (Skinner et al., 1999, p. 82). These spikelets were somewhat weathered so that such pigmentation had faded and was less prominent than on younger spikelets.

Albany County, Wyoming. Late June; grain in grain-ripe stage.

205. Stand of sheep fescue (Festuca ovina var. rydbergii= F. saximontana=F. brachyphylla subsp. saximontana)- One of the larger, ranker-growing grasses on the mixed prairie of the Front Range of the Central Rocky Mountains was sheep fescue for which the scientific name Festuca ovina var. rydbergii was used in Grasses of Wyoming (Skinner et al., 1999, p. 66, 68). This author-photographer did not encounter this species as other than a local dominant. It was not a widespread dominant species like Canby's bluegrass though it was a more abundant than Junegrass. Clements (1936, p. 258) interpreted Festuca ovina as oe of eight perdominants, widespread dominants that bind associations together into climaxes or, the synonym, formations) (Clements, 1936, ps. 258, 271). Some of the other perdominants that bound the five grassland associations into the were needle-and-thread, western wheatgrass, blue grama, sand dropseed, and Junegrasss (Clements, 1936, p. 258). However, Clements (1920) used F. ovina as an "umbrella species" to include the widespread F. idahoensis. This usage was consistent with the taxonomy and nomenclature of that time as, for example, in Coulter and Nelson (1909, p. 75) and as explained in Barkworth et al. (2007, p. 422).

The most recent and presumedly most authoritative (though not necessarily synonymous with most taxonomically correct) treatment of F.ovina was that in Barkworth et al. (2007, ps. 428-432) in which F. ovina was was restricted to a species introduced into North America from Eurasia so that it was necessary to "transplant" all native forms, variants, etc. previously included with F. ovina into other Festuca species and subspecies. Into which of these one or more species and/or subspecies F. ovina var. rydbergii belongs was not explained in Barkworth et al. (2007, p. 422). If F. ovina var. rydbergii was "transplanted" according to the taxonomic organization in Flora of North America it seemed that F. saximontana or F. brachyphylla were the most likely candidates. Or perhaps the older taxon of F. brachyphylla subsp. saximontana was more likely to be the correct taxon for F. ovina var. rydbergii. Hitchcock and Chase (1951, p. 74) showed F. saximontana as an earlier binominal for F. ovina. Kaul et al. (2006, p.676) used F. saximontana for specimens in the far western Nebraska Panhandle that had previously been identified as (Festuca ovina var. rydbergi, but Skinner et al. (1999, p. 67-68) retained (Festuca ovina var. rydbergi for specimens and plants on Wyoming range up to subalpine elevations.

Whatever the most nearly scientifically correct scientific name, this is a large fescue of one kind or another that was locally dominant over foothills mixed prairie.

Laramie County, Wyoming. Late June; grain-shatter stage.

206. Sheep fescue or, less commonly, Rocky Mountain fescue (Festuca ovina var rydbergii=F. brachyphylla subsp. saximontana=F. saximontana or F. brachyphylla, ?, or whatever)-Examples of the robust fescue (whatever the species, subspecies) that was a local dominant on mixed prairie in the foothills of the Front Range, a transition zone between Great Plains grassland and Rocky Mountain forests and parks.

Laramie County, Wyoming. Late June; hard-dough to grain-ripe phenological stages.

207. Panicle and spikelets of sheep fescue- Flower cluster and its fundamental units, spikelets, of some large and robust, Festuca taxon that was an important local dominant on mixed prairie in the foothills that functioned as an ectone between Central Great Plains grassland and Rocky Mountain forests, shrublands, and meadows. Based on the grass manual for Wyoming (and published by that state's land grant university) this plant was Festuca ovina var rydbergii. It was not clear (at least to this author) to which taxon this fescue fit in Barkworth et al. (2007, ps. 428-432), but most likely F. saximontana or F. brachyphylla.

Laramie County, Wyoming. Late June; hard-dough to grain-ripe stages of phenology.

Something to ponder (or, maybe, an imponderable): In addition to the infinite scientific phenomena there is the phenomenon of science itself, especially the scientific method. Disussions above (and elsewhere in this publication) made it clear that the matter of nomenclature and systematic arrangement of taxa is a matter that remains far from settled. This author suspects that such will never be settled--and certainly not ever to the satisfaction of all concerned. Sciencies is, afterall, a human affair and therefore subject to features of human nature including an array from admiration through envy, jealousy, and contempt as well as independent thought and defense of such thought. The nature of science is that mere mortals cannot know absolute truth, though in theory that ultimate goal becomes asyomptic. The author of Range Types suspects that in addition to, if not trumping, these aspects there is the matter of earning a livelihood (at least enough of one) so as to be permitted to continue a career in science.

As long as a sizeable part of that livelihood is contingent upon publication, especially numbers of peer-reviewed publications, it is seemingly impossible that the matter of scientific names for various taxa will ever be scientifically decided. At least not to the degree that matters of science are ultimately solved and a point of inquiry closed as is the case in "pure sciences" like Physics or Mathematics. Based on a reading of the history of Agrostology (all fields of Systematic Botany for that matter), numerous examples of which were noted herein, it seemed certain to the current author that the matter of scientific names of taxa will never be resolved. There is simply too much money (relatively speaking; by academic standards of living) to be made garnering another publication by simply pointing out that such and such a binominal was in error and "my latest research" (ie. my for-promotion-publication) showed that the more-nearly correct (better in some way) scientific name was thus and such (ie. Poa canbyi is really just an ecotype of P. secunda subsp. secunda).

Even certain areas of the Life Sciences can resolve a question in the science of Life. Biochemists elucidate and settle permanently the details of metabolic pathways. Eventually, after adequate experimentation and related forms of scientific inquiry the last enzyme or the final cofactor is fitted into the pathway puzzle and we move on to other uncharted biochemical seas. Not so taxonomists. They hash and rehash and then go back to the original hash never to settle the matter. Anatomy eventually becomes a "dead field for further research". There are professors of anatomy (at least professors who teach Anatomy), but they conduct research in related though different fields. Not taxonomists. They contemplate the femur, rationalize why the name of femure was in in error, should not have been named femur, and finally conclude (show scientifically as it were) that femur it is just the skeletal equivalent of an ecotype of the pelvis. Presto, another publication (for tenure, promotion, or at least a little bump up in salary).

As long as no more species are being discovered and written up (the typical situation, especially for vascular plants, in well-studied, thoroughly explored country) the only to get more publications is to rename and/or phylogenetically rearrange the know species. The alternative is to "close the herd book" on research in Plant Taxonomy, and provide much less employment for taxonomists (as is now the the situation for anatomists). Instead, agrostologists discover and map clades, which ties Plant Systematics to Molecular Biology (so it is bound to be more scientific, right?), and requirements for survival (Publish or Perish) are met.

That explains the winners in the taxonomy racket as it is currently practiced by some of its steller practitioners. The losers are just about everybody else. Ecologists, range and forest scientists, agronomists, even botanists besides taxonomists have to become fluent in both the old and new languages for which one traslation is incongruent with the preceding translations. What actually did this ecologist mean when he used the binominal Festuca ovina?. Some nomenclatural changes are essential and actually reduce confusion, but others gain little if anything except to create more confusion. The first (and maybe the last) description of some unit of vegetation was made when this taller, bigger-clumped bluegrass was Poa canbyi and this littlier bluegrass was Poa sandbergii. Now decades later, how can another vegetation scientist know whether P. secunda subsp. secunda was the P. canbyi or P. sandbergii or just plain P. secunda used by the earlier describing scientist?

Finally, ponder this. How can so many outstanding (supposedly) agrostologists look at the same plant (same taxonomic entity), even the same type specimen, and interpret it in so many different ways. How can one agrostologist or group of agrostologists conclude that the same plant (or specimen) is a different species, in a different species, or even in another genus than the one chosen by preceding agrostologists? They even construct dichotomous keys based on readily observed and key morphological features that lump and split and relump in as many different arrangements as there are taxonomists doing the arranging. Hitchcock and Chase (1951) saw this plant as this, Gould (1975) saw it as that, and Barkworth et al. (2007) saw it a third way. Is Taxonomy mostly in the eye of the beholder? If so, is this really science? How can instructors present Plant Systematics as solid science to undergraduates when there are four names for Canby's bluegrass in four different manuals all written by agrostologists? Do agrostologists ever ponder this? Do they care?

208. Tufted fleabane (Erigeron caespitosus)- This specimen of a widely distributed DWC (Damn White Composite) was growing on the Canby bluegrass-Wyoming threetip sagebrush-dominated, foothill mixed prairie range presented above. The head of this species is typically disproportionately large for the rest of the shoot which makes it a conspicuously showy forb though one of relatively restricted species range.

Erion is Greek for wool which was obviouly in reference to pubescence of s

Albany County, Wyoming. Late June; peak bloom stage of phenology.