Texas Edwards Plateau

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The Edwards Plateau, called affectionately the Texas Hill Country, is one of Texas’ major Vegetational or Land Resource Areas. Unlike some of the Vegetational Areas (Blackland Prairie, Cross Timbers and Associated  Prairies, Post Oak Savanna, Pineywoods, and Coastal Prairies and Marshes) which are biotic or floristic units or designations, the Edwards Plateau (along with the Trans Pecos Basin and Range and High Plains Vegetational Areas) is a geologic unit, a delineation based on physiographic province, and not a biological unit. Therefore, there is less botanical unity in the Edwards Plateau range types and sites. Included within the Edwards Plateau Region is the granitic Central Basin, the Stockton Plateau, and the Balcones Escarpment. The exact physiographic units to include as part of the Edwards Plateau remains uncertain with various authors using different criteria and, thus, including different locations (Riskind and Diamond in Amos and Gehlbach, 1988, ps. 1-5). For example, some authors included the Stockton Plateau as part of the greater Edwards Plateau while other authors interpreted the Stockton Plateau as part of the Trans-Pecos Basin and Range province (hence the Vegetational or Land Resource of that name). Strictly speaking the Stockton Plateau is part of the Great Plains physiographic province (details below) and not part of the Basin and Range Province (Fenneman, 1931, p. 50). Based on that geologic ("bedrock") basis the current author herein treated the Stockton Plateau as part of the Edwards Plateau. This treatment was inconsistent with some workers cited in Amos and Gehlbach (1988, p. 2), but there was inconsistency even within Amos and Gehlbach (1988, ps. 2, 25). Inclusion of the Stockton Plateau as part of the Edwards Plateau was consistent with the traditional designations of Texas Vegetational Areas (Gould, 1962, ps. 1, 11; Correll and Johnston, 1979, map 1, ps. 9-10, 12). Western (semiarid) and southern boundaries of the Edwards Plateau (with eastern border of Trans-Pecos Basin and Range Region and plains of Rio Grande) as a natural spatial unit describing range vegetation is even more confused and complicated. There is not complete agreement (ie. matching overlap) between the physiographically defined Edwards Plateau vegetational area with the corresponding potential natural vegetation (Kuchler, 1964, map in Garrison et al., 1977) and level III ecoregions (Griffith et al., 2004). As cited in the preceding paragraph, Texas range scientists, primarily taxonomists and plant ecologists (Gould, 1962, ps. 1, 11; Correll and Johnston, 1979, map 1, ps. 9-10, 12), traditionally mapped the Edwards Plateau as a vegetational or land resource area that extends far west of the Pecos River (almost to the Big Bend of the Rio Grande) and as far south as the Rio Grande. By contrast, Kuchler (1964; map in Garrison et al., 1977) extended the Chihuhuan Desert of the general Trans-Pecos Basin and Range south of the Edwards Plateau savannahs (to the Rio Grande) and eastward to contact the northwestern tip of the Rio Grande Plains while adding a ceniza (Leucophyllum frutescens)-dominated scrub savanna farther east and along ridges and floodplain of the Rio Grande. Griffith et al. (2004) mapped the Chihuhuan Desert, Edwards Plateau, and Rio Grande (Southern Texas) Plains ecoregions (level III) in similar mapping fashion to, though not in complete agreement with, units of natural vegetation (Kuchler,1964; map in Garrison et al., 1977). Griffith et al. (2004) extended the Chihuhuan Desert contacts along the Rio Grande clear to the Rio Grande Plains with an Edwards Bajada level IV ecoregion of the Rio Grande (Southern Texas) Plains and not of the Edwards Plateau ecoregion. Neither the potential natural vegetation (maps of Kuchler, 1964; in Garrison et al., 1977) nor the ecoregion of Edwards Plateau (Griffith et al., 2004) extend to the Rio Grande or to the Pecos River. A similar situation of confusion exist with regard to placement of the Lampasas Cut Plain into a vegetational or land resource area. Historically the Lampasas Cut Plain was interpreted as part of either of the Edwards Plateau or of the Cross Timbers and Prairies vegetational area. Traditionally prominent Texas authorities (Gould, 1962, ps. 1, 10, 11-12; Correll and Johnston, 1979, Map 1, ps. 7, 9-10; Griffith et al., 2004) regarded the Lampasas Plain as part of the Cross Timbers-Grand Prairie, but notable exceptions, including authors in Amos and Gehlbach (1988, ps. 1-5, 12, 15, 57, 76, 116, 118) and Texas Parks & Wildlife (various undated vegetation maps), placed the Lampasas Plain in the Edwards Plateau. Based on physiography (= physiographic provinces)-- the second most distinguishing criterion after climate in designating major units of vegetation-- placement within the Edwards Plateau is most precise. Fenneman (1931, p. 55-56) distinguished the Lampasas Cut Plain from the Edwards Plateau, but he (Fenneman, 1931, ps. 55-56; Fenneman, 1938, ps. 100-101, 106) included both the Edwards Plateau and the Lampasas Cut Plain as parts of the Great Plains physiographic province while the Eastern and Western Cross Timbers and Grand Prairie were included in the Coastal Plains physiographic province (Fenneman, 1938, ps. 100-106). Fenneman specified that even though the Lampasas Cut Plain "is genetically a part of the Coastal Plain" (Fenneman, 1938, ps. 100-101) this physiographic unit was "assigned to the Great Plains province" (Fenneman, 1938, p. 106). Clearly the Lampasas Cut Plain is aligned more closely physiographically with the Edwards Plateau than with the Cross Timbers and Grand Prairie. This affinity becomes even stronger when reference is made to the more general or greater Edwards Plateau. It might be helpful as regards designation and inclusion of physiographic provinces, vegetational areas, ecoregions, range types, etc. to explain that a further confounding factor is that of counties (in this case, Texas counties). In rural areas, the county is the fundamental unit of government. This is especially true in regard to activities by the Texas Agricultural (Cooperative) Extension Service (ie. county agent offices) and related functions of the land grant university as well as various activities by United States Departmsnes of Agricultural and Interior. Soil surveys, including range site descriptions, by the (Soil) Natural Resorces Conservation Service and various cooperting organizations are usually compiled by or as to county. Delineation of a natural unit like the Edwards Plateau is often on basis on a political uint, the county. Thus, some important aspects of the Edwards Plateau were studied, explained, or mapped roughly by county lines in Amos and Gehlbach (1988, Fig 1, ps. 26, 32, 33, 35, 36, 39). Each of the different general units or divisions of the Edwards Plateau has a distinct overall (and component) vegetation. There are transitions in vegetation where the Edwards Plateau joins the other Vegetational Areas like the Cross Timbers, Rolling Red Plains, and Trans-Pecos Basin-Range, the latter Area designated by proper title of the Basin and Range physiographic province. This subdivisions (Amos and Gehlbach (1988. ps. 1-6) were indicated in the treatment below. It was explained previously that the Edwards Plateau is part of the Great Plains physiographic province which in Texas also includes the High Plains (= Staked Plains or Llano Estacado) and Rolling Red Plains. The Balcones Escarpment that formed along the Balcones Fault Zone is the extreme edge of the Edwards Plateau and this scarp forms the southern and eastern boundaries of the Great Plains province where this physiographic unit joins the Gulf Coastal Plain physiographic province (Fenneman, 1931, ps. 51, 53-55; Fenneman, 1938, ps. 100, 102; Hunt, 1974, ps. 210, 224, 228, 243, 326, 341; Trimble, 1990, ps. 46-48). Geographic location, especially in relation to other physiographic provinces, as well as geologic/edaphic features combined with a similar "hodge-podge" of climatic variables are causative agents in formation of the unique vegetation of the diverse Edwards Plateau. There were early accounts of Texas vegetation including some reference to the Edwards Plateau. The reader is referred to the translated or edited journals of Olmsted (1857; later editions available such as that of Rybczynski, 2004), Roemer (Mueller, 1935), Lindheimer (Gohne, 1991), Riddell (Breeden, 1994). Irrespective of these excellent descriptions, the overall vegetation— if there was one or, even, several general forms — was far from clear largely because Edwards Plateau did “not appear in any pre-1860 description of Texas” (Weniger in Amos and Gehlbach, 1988, p. 19). Weniger (p. 21) noted: “There is not one early report of completely open country on the Edwards Plateau”.  He concluded:

“The historic Plateau was thus a blend zone with woody vegetation predominating  northward in proximity to the wooded Crosss Timbers and grasslands predominating near the eastern Blackland, southern Coastal, and western short-grass prairie regions” (Weniger in Amos and Gehlbach, 1988, ps. 22-23).

The definitive work on Edwards Plateau range is Edwards Plateau Vegetation- Plant Ecological Studeis in Central Texas (Amos and Behlbach, 1988). Highly recommended. Arrangement of range vegetational units in coverage below followed this reference as modified by Correll and Johnston (1979) which followed traditional demarcations.

Historical and Tecnhical Note: Texas' Edwards Plateau is but one of ten or eleven (depending on authority doing the counting) natural subdivisions of the state that over a number of years have been designated variously as "vegetational areas", "land resource areas", and, more recently, "natural regions and subregions". Obviously in geographical scale and cartography usage the former or older designtions are more accurate and correct conventions than the "up-to-date" distinctions (typical, hugh?) given that spatial scale of mapping units is less than that traditionally used for regional size. Mapping of Texas natural areas has been a long-standing endeavor that likely traces back to travels and journals of the first explorers and scientists. Modern attempts are usually accorded to the Catalogue of the Flora of Texas (Cory and Parks, 1937) and The Vegetation of Texas (Tharp, 1939) followed by Texas Plants-- A Checklist and Ecological Summary edited by Gould (1962) and Manual of the Vascular Plants of Texas by Correll and Johnston (1979). In addition to the traditional ten or so areas of these publications, recent efforts were made to delineate smaller map units (ironically using the title of "region" which is the designation for geographic size larger than area) of natural communities and/or landscapes under auspices of The Natural Heritage Policy Research Project through the Lyndon B. Johnson School of Public Affairs at the University of Texas, Austin (1978) and available "on line" through Texas Parks & Wildlife. This latter project is but the most recent of several studies into the natural resources of Texas. In this regard see for example the report, Texas Looks Ahead-- The Resources of Texas (University of Texas, 1944, pgs. 273-282). A side issue but an interesting lesson in politics was presented by these two reports. Former United States Presidents have ways of getting their names attached as memorials to things that were already being done or created with little or no benefit from the previous Chief Executive. LBJ was clearly a master of this situation. A similar case in point was the Cross Timbers National Grassland that was renamed the LBJ National Grassland even though it was President Franklin Delano Roosevelt and not Lyndon Baines Johnson who was responsible for creation of this part of the National Forest System. One of the most recent exercises in mapping of Texas "natural areas or regions" was the the multi-agency project that produced the map, Ecoregions of Texas (Griffith et al., 2004). Unfortunately (perhaps unavoidably) some the level III and level IV ecoregions were inconsistent with other (older but sometimes more precise) designations and delinations. For example, the Stockton Plateau Ecoregion (Level IV) in Griffith et al. (2004) does not coincide completely with the southern portion of the Stockton Plateau as a land form and geologic unit (see Figure 2 in Amos and Gelbach, 1988, p. 4).

1. Edwards Plateau live oak-grassland savanna- Texas Edwards Plateau, a section of the Great Plains physiographic province, has traditionally been treated as a vegetational or land resource area. However, it does not correspond closely to kinds of vegetation. The Edwards Plateau is a geologic unit. It is a single block of limestone existing as a stripped plain but this consist of several subregions, each supporting a different form or kind of vegetation. Here is the oak-juniper mixed prairie savanna. It consist of dominant live and post oaks along with such junipers as redberry cedar (Juniperus pinchotii) and blueberry, post, or Ashe cedar (J. ashei) and many grass species ranging from little bluestem (Andropogon scoparius= Schizanchyrium scoparium), Canada wildrye (Elymus canadensis), Texas cupgrass (Eriochloa sericea), plains lovegrass (Eragrostis intermedia) and green sprangletop (Leptochloa dubia) to buffalograss (Buchloe dactyloides), curly mesquite (Hilaria belangeri), and various gramagrasses including sideoats grama (Bouteloua curtipendula), blue grama (B. gracilis), hairy grama (B.hirsuta) tall grama (B. pectinata), and red grama (B. trifica). Vine mesquite (Panicum obtusum), several perennial threeawn species, and the ever-present cool-season Texas wintergrass are major grasses. Introduced and now naturalized forbs include red-stem filaree or storksbill. Typically there are always some actively growing forage species in this portion of the Edwards Plateau. Menard County, Texas. June. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-Oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

2. View of the Llano area or subregion of the Edwards Plateau (generally referred to as Llano Uplift)- This massive granite uplift is the famous Enchanted Rock. Rislind and Diamond (in Amos Gehlbach, 1988, p. 5) explained the uniqueness of this part of the Edwards Plateau: "The Llano Uplift is strinkingly different from the remainder of the Edwards Plateau. It is an intrusive outcrop of Precambrian granitic material". Vegetation is essentially the same as in the oak-juniper savanna unit except trees are often more dense with a greater component of mesquite and other woody plans such as the lianas of various grape (Vitus) species. Llano County, Texas. October. FRES No. 32 (Texas Savanna Ecosystem). K-78 (Mesquite-Oak Savanna). SRM 734 (Mesquite-Oak) variant. Edwards Plateau Llano Uplift Ecoregion, 30b (Griffith et al., 2004).

General Edwards Plateau, including Oak-Juniper Savanna and Lampasas Cut Plain

3.Tallgrass prairie on Lampasas Cut Plain- Prairie landscape and range plant community presented in this photograph was more typical of the Kansas Flint Hills and Oklahoma Osage Questas than the Texas Edwards Plateau, but as was described and explained in the introduction to the Edwards Plateau the Lampasas Cut Plain is part of the Great Plains and not the Central Lowlands physiographic province. Given that physiographic relations are second only to those of climate, range vegetation of the Lampasas Plain was most precisely or properly placed in the Edwards Plateau rather than in the more physiogonomically similar Cross Timbers and Prairies and/or Blackland Prairie vegetational (= land resource) areas. The analamous tallgrass prairie climax community (= potential natural vegetation) of the Lampasas Cut Plain contrast dramatically with the tree/shrub-mixed grass savanna of the rest of the Edwards Plateau. Floristic and vegetational distinctiveness of the example of virgin climax little bluestem-meadow dropseed grassland show above was introduced early in this series to emphasize the diversity of range vegetation within the Edwards Plateau and to show the botanical affinity of Edwards Plateau range types with those of the Texas Blackland Prairie and Cross Timbers and Prairies area. Affinity in species composition and structure was greatest between grasslands of Lampasas Cut Plain and Grand (= Fort Worth) Prairie. .The pristine tallgrass prairie shown here was actually more a mixture of both tallgrass and mid-grass species with shortgrass species also well-represented. Co-dominants were clearly little bluestem and meadow dropseed (Sporobolus asper var. drummondii= S. asper var hookeri= S. pilosus), but the midgrasses silver bluestem (Andropogon saccharoides= Bothriochloa saccharoides) and sideoats grama and the shortgrass hairy grama were obvious associates. Purple threeawn (Aristida purpurea) was also widely distributed. Other Sporobolus species were widespread on this range including purpleflower dropseed (S. clandestinus) and poverty dropseed (S. vaginaeflorus). Indiangrass (Sorgastrum nutans) was present in small proportions, but it served as an indicator species typical of tallgrass-dominated prairie communities. The major forb was elegant gayfeather (Liatris elegans) while annual broomweed (Gutierrezia draculoides), the second most common forb, gave the Compositae its usual domination of the forb category. With a range plant community in which tall-, mid-, and shortgrass species were well-represented this grassland resembled (to a degree) a mixed prairie typical of climax Great Plains grasslands in the Rolling Red Plains vegetational area, but dominance by tallgrass species and physiogonomy indicative of tallgrass vegetation clearly distinguished this as tallgrass (vs. mixed) prairie. This range was most likely in the high Good (possibly low Excellent) range condistion class based on the classic Dyksterhuis (1949) Soil Conservation Service model of range analysis. Lampasas County, Texas. October, autumnal aspect. FRES No. 39 (Prairie Grassland Ecosystem). K-66 (Bluestem Prairie). Variant of SRM 710 (Bluestem Prairie); the Bluestem-Dropseed rangeland cover type (SRM 708) is descriptive in title only as this latter is a semiarid cover type of sandy soils (Shiflet, 1994). Bluestem"Tall-Grass" Series of Plains Grassland biotic community of Brown et al., 1998). Limestone Cut Plain Ecoregion 29e (Griffith et al, 2004).

4. Edwards Plateau pristine range vegetation- This is the Edwards Plateau mixed prairie-live oak savanna. This form of the Edwards Plateau range ecosystem is obviously more grassland than shrubland. It should logically have been arranged under the Grassland and not the Shrubland Biome slides. It was placed here for consistency so as to keep all the Edwards Plateau examples together even though the Edwards Plateau Vegetation (= Land Resource) Area of Texas is a geologic-based and not a biological- or botanical-based unit. This placement is consistent also with the forest and range ecosystem descriptions of Garrison et al. (1977, ps. 39-41) who placed the Edwards Plateau range communities under the Texas Savanna Ecosystem, FRES No.32, which they arranged under Shrubland Ecosystems and not Grassland Ecosystems.  This “mint condition” example of the Edwards Plateau grassland–savanna was the vegetation described by John Leonard Riddell, a university professor and medical doctor, who was the first trained naturalist-scientist to visit and describe the Texas Edwards Plateau (Breeden, 1994, p.xi):

“The musquit (mesquite) tree now disappears and is replaced by live oak, post oak, etc. The country becomes more & more hilly … Land sparsely timbered, but no uninterrupted large prairies. Real thickets occur only in the canadas or ravines of water courses” (Riddel journal entry of 25 October, 1839 as edited by Breeden,1994, ps. 58-59).

This is mixed prairie with the dominant tallgrass species being little bluestem with Indiangrass and Canada wildrye the associates of the tallgrass prairie plants. Sideoats grama, vine mesquite (Panicum obtusum), silver bluestem, and Texas wintergrass (Stipa leucotricha) are dominant midgrass species while buffalograss, curly mesquite (Hilaria belangeri), hairy grama, red grama (Bouteloua trifida), and Texas grama (B. rigidiseta) are abundant on openings among the dominant bunchgrasses. Wrights and purple threeawn are present but relatively rare in this Excellent range condition class community. The dominant tree species is the scrub live oak or plateau oak (Quercus virginiana var. fusiformis= Q. fusiformis). Post oak is the associate while mesquite and juniper are widely scattered.  Note presence of sheep and the absence of a pronounced browse line even though oak leaves are palatable to sheep and the white-tail deer that are “thick as hops” in the Texas Hill Country. An example of excellent stewardship on a private ranch.  McCullough County, Texas. Late estival aspect, June. FRES No. 32 (Texas Savanna Ecosystem), mapped as K-77 (Juniper-Oak Savanna) or 78 (Mesquite-Oak Savanna), but this pristine range lacks the dual scurge of juniper and mesquite. SRM 734 (Mesquite-Oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

5. Physiognomy of Edwards Plateau mixed prairie-live oak savanna range- Community scale view of the live oak phase of Edwards Plateau savanna. Dominant grass was little bluestem, in fact a little bluestem consociation with Indiangrass as associate species. Texas parks and Wildlife Kerr Wildlife Management Area, Kerr County, Texas. October. Autumnal aspect. FRES No. 32 (Texas Savana Ecosystem). K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-Oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

6. Edwards Plateau mixed prairie-live oak savanna range community- Species composition of the live oak-dominated phase of Edwards Plateau savanna range. Texas Parks and Wildlife Kerr Wildlife Management Area, Kerr County, Texas. October. Autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-Oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

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7. Edwards Plateau mixed prairie-oak savanna- Live oak was the dominant, almost exclusive, woody species except for post oak which was the associate woody species while little bluestem was the dominant understorey herbaceous species (Indangrass was associate herbaceous species) on this relict Edwards Plateau vegetation. Abundant regeneration of both oak species, but reproduction was greater for live oak which was the local dominant. Gillespie County, Texas. October. Autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

8. Edwards Plateau savanna range plant community- In this relict Edwards Plateau range vegetation the locally dominant live oak formed a canopy consociation while the understorey was dominated by little bluestem with Indaingrass as the associate. Both tallgrass species were conspicuous in foreground as were larger seedlings of live oak. Two other-- though infrequent-- woody species were the shrubs algerita, algarita, or algerita thorn (Berberis trifoliolata= Mahonia trifoliolata) and lime pricklyash or tickle-tongue (Zanthoxylum hirsutum). Relict vegetation, and at peak standing crop at end of a wet summer. Rare view all the way around. Enjoy while it last! Gillespie County, Texas. October. Autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-Oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al, 2004).

9. Edwards Plateau savanna range at peak standing crop- Two scenes of the post oak-dominated phase of Edwards Plateau mixed prairie-oak savanna with dominant tallgrasses at hard seed phenological stage. Dominant understorey herbaceous species was little bluestem (pretty much a little bulestem consociation) with Indiangrass as associate. Live oak was the associate woody species. Pristine vegetation at end of a wet summer. Ultimate expression (climax plant community) of Edwards Plateau savanna range. Gillespie County, Texas. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-Oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

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10. Edwards Plateau savanna as the Commanche knew it- Pristine mixed prairie-oak savanna range with post oak and live oak the dominant and associate, respectively, woody species and little bluestem and Indiangrass the dominant and associate, respectively, herbaceous species of the understorey. Kerr County, Texas. October. Autumnal aspect. Tallgrass species in hard seed phenological stage. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

11. Relict Edwards Plateau range plant community- Climax mixed prairie-oak savanna with post oak the dominant and live oak the associate woody species and little bluestem the dominant and Indiangrass the association herbaceous species. "It does get any better than this". Textbook species compostiton of the more mesic and northern portion of Texas Edward Plateau. Gillespie County, Texas. October. Autumnal aspect; peak standing crop of understorey. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-Oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

12. Inside climax Edwards Plateau savanna range- Post oak-dominated phase of one of the more mesic and northern parts of the Edwards Plateau (live oak was the associate woody species). No mesquite or juniper in this relict stand. It was range like this that once made the Edwards Plateau, the fabled "Texas Hill Country" a fabulous and famous grazing ground for numerous species of livestock and wildlife. Note dense colony of Indiangrass in right foreground. Scrub tree form of post and live oaks was typical of growth habit of these species in this range type. Gillespie County, Texas. October. Autumnal aspect.

13. Edwards Plateau mixed prairie- Natural grassland expressions (subtypes) of range are relatively rare in the Edwards Plateau being mostly restricted (as was explained above) to the Lampasas Cut Plain portion of this Texas vegetational or land resource area of Texas. This is expecially the situation in post-white man times with ever-increasing brush invasion. The relict range vegetation presented here was a mixed (tall-, mid-, and shortgrass species) prairie form of grassland that occurred within a general live oak-grass savanna visible in the background. The local range plant community shown in these two photographs consisted of little bluestem as the major tallgrass species with Indiangrass, Canada wildrye and various perennial dropseeds being other native tallgrass species and Johnsongrass as a naturalized tallgrass. Midgrasses included silver bluestem, sideoats grama, Texas wintergrass, and Texas cupgrass. Major shortgrass species were hairy grama, curly mesquite, and buffalograss. The most common shrub was soapweed (Yucca glauca) and grassland pricklypear (Opuntia macrorhiza). There were almost no forbs: annual broomweed (Gutierrezia dracunculoides) was the most abundant forb species. Menard County, Texas. October (under gray sky midway through an early norther); peak standing crop. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). A grassland variant (form) of SRM 733 (Juniper-Oak). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

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14. Edwards Plateau live oak-cedar savanna- Plateau live oak and post, blueberry, or Ashe juniper (usually called known as post etc. cedar) formed a prominent layer of low trees and/or shrubs on an otherwise mixed prairie grassland of mostly mid- and shortgrass species (primarily sideoats and hairy gramas, Texas wintergrass, curly mesquite, and buffalograss with substantial though lower cover of little bluestem, green sprangletop, and Texas cupgrass). This range had been useed for many years (decades) by sheep, goats (Angoras), and whitetail deer such that there were relatively few forbs in the herbaceous understorey. In fact, this small ruminant range had been so heavily browsed as to result in a conspicuous browseline, a situation known as "highlining". The major (and about the only) shrub species with reach of a goat or deer standing on his hind legs was some subspecies of common Texas, Engelmann's, or Lindheimer's pricklypear (Opuntia engelmannii= O. lindheimeri: nomenclatural treatment of this Opuntia group has been a long-running taxonomic feud skirmish that may never be settled). This range was in Good range condition class with less cover and density of tallgrass species (aconversely, more of mid- and shortgrass species) than in climax vegetation. Palatability of Ashe juniper (which is substantially greater than that of Juniperus pinchotii) was obvious from the two highlined trees featured in this slide. Schleicher County, Texas. October, and a very wet one; autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

15. Live oak-mixed prairie savanna- Sideoats grama was dominant, but there was also high cover and density of silver bluestem, hairy grama, buffalograss, curly mesquite, Texas wintergrass, and various perennial dropseeds. These were the major species except in herbaceous understorey of live oak mottes where Texas cupgrass, Canada wildrye, Texas wintergrass, and green sprangletop were local dominants depending on microsite. Some subspecies of Texas, Engelmann's, or Lindheimer's pricklypear was the associate shrub. This was strictly cattle and whitetail deer (the only ungulate species) range resulting in more live oak biomass at browse height (reflecting relatively low degree of use of live oak by cattle). Also at the relatively low or conservative stocking rate on this range there had been very little grazing beneath live oaks such over time the more palatable tallgrass and midgrass species came to dominate the understorey of live oak mottes. This was a textbook example of proper degree of use (generally the most important of the Four Cardinal Principles of Range Management) and consequent wise use management. Range condition class was high Good to low Excellent on this Shallow range site. Schleicher County, Texas. October of a wet late summer and early autumn (which enhanced expression of species composition of this range). FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

16. "Summary" (composite) species composition of a plateau live oak-mixed prairie savanna- An example of Edwards Plateau vegetation on a Shallow range site that was part of a cattle and wihtetail deer range used conservatively (fairly low stocking rate) in a wet late summer-early autumn. Major grass species (in approximate relative composition) were sideoats grama, curly mesquite, silver bluestem, hairy grama, Texas wintergrass, Texas cupgrass, and perennial dropseeds. Little bluestem and Indiangrass (potential associate or dominant grasses) were present in small amounts, but invaders like perennial threeawns and red grama occurred at much smaller proportions. Texas or Engelmann pricklypear was the associate shrub to live oak. Forbs were almost non-existant suggesting that at one time this range had been stocked heavily with sheep and goats. Range condition class was Good and degree of use was light. Students should "read sigh" and carefully observe that live oak foliage was regenerating on previously "highlined" (having high browse heights) oaks. All-in-all: sound, wise use management with subsequent restoration of range resources. Schleicher County, Texas. October of a wet late summer and early autumn (which enhanced expression of species composition of this range though it certainly did not determine botanical make-up). FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

17. Beneath the live oaks- Herbaceous understorey of a motte of plateau live oak on lightly stocked cattle and deer range was dominated by Texas cupgrass, Canada or nodding wildrye, Texas wintergrass, silver bluestem, and sideoats grama (in about that relative order) with conspicuous but considerably less cover of green sprangletop and little bluestem. Schleicher County, Texas. October of a wet late summer and early autumn (which enhanced--but did not determine--the expression of species composition of this range). FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

18. Still under the live oaks- Sward of herbaceous layers of the plateau live oak motte preented in the immediately preceding photograph. In this slightly different "photo-plot" the major species were (in estimated approximate order) Texas cupgrass, Canada or nodding wildrye, Texas wintergrasss, and green sprangletop with lesser cover of sideoats grama, silver bluestem, and, with least cover, little bluestem. On this Shallow range site, this species make-up constituted Good range condition class. Degree of use was extremely light which was a combination of abundant recent rains and low (conservative) stocking rate. Obviously there is much truth in the adage that abundant and advantageously timed rainfall can compensate for some management sins, but this is, of course, limited. All the rain in the world could not explain the botanical composition of this range. Edwards Plateau savanna vegetation. Good stewartship explained this gem of Edwards Plateau savanna vegetation. Schleicher County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

19. Typical Edwards Plateau mixed prairie-oak-juniper savanna range- In the more central portion of the Edwards Plateau the mid- and shortgrass species are more prominent while the tallgrass species are less common than in the more northern and eastern portions. One of the most influencial environmental variables of the Edwards Plateau Region is frequent severe drought. This is exacerbated by the shallow, stony soils overlying the granite or limestone bedrock. An appropriate caption for this slide would have been “A Dry Spring in the Edwards Country” to describe the protracted winter-drought dormancy phase seen here. This is May on a Good range condition class range grazed by cattle, sheep, goats, and white-tail deer. Little bluestem, silver bluestem, sideoats grama, curly mesquite, buffalograss, and several grama species make up a mixed prairie undertstory to the savanna woody layer of scrub live oak or plateau oak with scattered juniper trees. The range should be green this time of year, but all grass species are either still dormant or, in the instance of the cool-season species like Texas wintergrass, recently browned upon completion of their yearly cycle. The large green clumps are sacahuiste (Nolina texana) which if eaten in large enough quantities can cause secondary photosensitization (skin lesions due to liver damage) and kidney damage.   This is a study pasture in a stocking rate trial on the famous Texas A&M University System Sonora Experimental Range (Edwards County, Texas). It has been stocked for the past five years at 32 Animal Units per Section (640 acres) which is regarded as moderate stocking for this range site. Note the moderate highlining of the live oaks. At first flush this rangeland looks to be in “tough shape” due to drought and a fairly uniform and relatively “short”, even “close”, degree of use. This is a case where “looks are deceiving”. The species composition includes high levels of little and silver bluestem (the portion with grass clumps at left midground extending across in front of the center clumps of live oaks) while the shorter-cropped grasses in the foreground are dominated by sideoats grama and curly mesquite with relatively low proportions of invaders like red and Texas gramas. This is an example of proper use management that allows for adequate ground cover (against the torrential rains that often break a drought) of decreaser and increaser species even after prolonged drought.

“In Texas the savy rancher is either in a drought or preparing for one”.                                                                                --- An old and very wise Texas saying. FRES No. 32 (Texas Savanna Ecosystem), K-77 (Juniper-Oak Savanna), SRM 734 (Mesquite-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

20. Typical scene of Edwards Plateau range- Common use (Rambouillet sheep, Boer goats, and whitetail deer were the major species) of a live oak-juniper mixed prairie savanna in central Edwards Plateau. On this Fair condition range tallgrasses like little bluestem and Indiangrass were extremely limited, some midgrasses like silver bluestem were also uncommon while others like sideoats grama and plains lovegrass were locally abundant, and shortgrasses (curly mesquite, buffalograss, hairy grama) were generally dominant. This small trap was close to ranch headquarters and frequently received heavy use. Shrubs present at relative covers of invader status included Texas, Englemann or Lindheimer pricklypear; agarito; and honey mesquite. Forb invaders were western ragweed (Ambrosia psilostachya) and silverleaf nightshade (Solanum elaeagnifolium). There was also something of a high browse line, though nothing like the 'highlined" browse so often present on Edwards Plateau ranges that are browsed by goats, deer, sheep, cattle, sundry exotic ungulates (and often God alone knowns what else). Texas A&M University Sonora Experiment Station, Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

21. About as close to pristine as it gits nowadays- Live oak-mixed prairie savanna with a botanical composition at (or close to) climax. Dominant grasses were silver bluestem and sideoats grama with plains lovegrass, Texas wintergrass, Texas cupgrass, cane bluestem (Andropogon barbinodis= Bothriochloa barbinodis var. barbinodis), little bluestem, and dropseed species also major grasses. Curly mesquite and buffalograss were much less plentiful than on adjoining ranges. There was relatively little threeawn and that was purple threeawn (Aristida purpurea complex). Occasional plants of King Ranch bluestem (Andropogon ischaemum= Bothriochloa ischaemum var. songarica) were present, but much more limited than was typical for this local area. The most common forb was redstem filaree (Erodium cicutarium). This was in contrast to abundant cover and density of western ragweed and silverleaf nightshade on adjacent ranges. There were scattered plants of the composite slender greenthread (Thelesperma simplicifolium). The Excellent condition class range presented in these two (and the succeeding plus two later photographs) was less than 300 yards from the Fair condition range in the immediately preceding slide. Texas A&M University Sonora Experiment Station, Edwards County, Texas. October, autumnal aspect. Peak standing crop for this range plant community. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

22. Edwards plateau savanna in top form- Another view of the climax live oak-juniper-mixed prairie savanna presented immediately above. Physiogonomy and structure of this multi-layered range vegetation was obvious with tallgrasses represented by little bluestem while silver bluestem, cane bluestem, sideoats grama, plains lovegrass, and Texas wintergrass were major midgrasses with curly mesquite, buffalograss, and hairy grama being the major shortgrasses. There were occasional plants of the invader grasses King Ranch bluestem and purple threeawn and increaser green sprangletop. The desirable naturalized Mediterranean forb, redstem filaree or stork's bill, was present as was the native invader, western ragweed. There was low density of naturalized Mediterranean annual grasses (Bromus spp.). Texas A&M University Sonora Experiment Station, Edwards County, Texas. October, autumnal aspect. Peak range biomass. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

23. Multi-species carpet of grass- Sward of the climax Edwards Plateau mixed prairie savanna shown in the three immediately preceding photographs. This Excellent condition range had three prominent layers of grass: 1) tallgrass represented mostly by little bluestem, 2) midgrass element consisting mostly of silver bluestem, sideoats grama, plains lovegrass, Texas wintergrass, and cane bluestem, and 3) shortgrass composed of curly mesquite, buffalograss, and hairy grama. Forbs were limited (likely resulting from grazing by sheep, goats, and deer) with the naturalized annual redstem filaree or stork's bill the major species. The very restricted invaders included purple threeawn, King Ranch bluestem, western ragweed, and silverleaf nightshade. Texas A&M University Sonora Experiment Station, Edwards County, Texas. October, autumnal aspect. Peak standing crop. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

24. Some of a lot- This photographic quadrant of the sward of the climax Edwards Plateau savanna range shown in the four slides immediately above included silver bluestem, curly mesquite, and buffalograss at peak standing crop and early growth redstem filaree. Multi-layers of the herbaceous part of this range type were distinct. Texas A&M University Sonora Experiment Station, Edwards County, Texas. October, autumnal aspect. Peak standing crop. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

25. Edwards Plateau savanna as it is best known- This arch-typical scene of oak-juniper mixed prairie savanna had a rougly 50:50 mix of redberry or Pinchot cedar (juniper) and blueberry or post or Ashe cedar (juniper) along with plateau live oak (as co-dominant) and honey mesquite that formed an arboreal layer while Texas, Lindheimer, or Engelmann pricklypear and agarito along with an occasional devil's head or cow crippler cactus (Echinocactus texensis) comprised a lower shrub layer. Both of these woody layers occurred as local individuals or small, scattered stands in a mixed prairie of three prominent herbaceous layers each dominated by a few to several species of native grassses. These grasses were primarily warm season perennials, but Texas wintergrass represented cool season perennials while cool season annual grasses included the naturalized Mediterranean species, Japanese chess (Bromus japonicus) and cheatgrass (B. tectorum), as well as the native annual, little barley (Hordeum pusillum). Annual grasses were more common on this range than on the range at or approaching the climax state in preceding slides. Naturalized warm season grasses were limited to the relatively scarce Johnsongrass and King Ranch bluestem. In context of Landscape Ecology live oak mottes and cedar stands were patches in a matrix of mixed prairie. Texas A&M University Sonora Experiment Station, Edwards County, Texas. October, autumnal aspect. Peak standing crop stage. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

26. Praise the Lord (especially for recent rains) and pass the drip tourch- Edwards Plateau live oak-juniper mixed prairie savanna invaded by Pinchot or redberry and Ashe or post junipers nine months following a winter (January) prescribed burn. Even the relatively cool winter burn top-killed almost every cedar (juniper) and all but the largest honey mesquites on this range (note two mesquites in second slide). This pasture had been grazed throughout the plant-growing seasons subsequent to the prsecribed fire. On this specific range tallgrass species like little bluestem, Indiangrass, and green sprangletop were relatively rare except for dropseed species so that the range plant community was primarily one of midgrasses (sideoats grama, silver bluestem, Texas wintergrass, plains lovegrass, common windmillgrass (Chloris verticillata), cane bluestem, and purple threeawn in that rough order) and shortgrasses (curly mesquite, buffalograss, hairy grama. There were scattered plants of the exotic King Ranch bluestem and Johnsongrass. Woody plants in addition to live oak, cedar, and mesquite included the cactus species, Texas or Engelmann pricklypear and tasajillo (Opuntia leptocaulis), agarito, and Texas persimmon. Tasajillo, including the largest plants, had been topkilled by the prescribed burn, but many of the larger clumps of pricklypear had most shoots spared. Also, individual plants of the low-growing Devil's head or cow (horse) crippler cactus had been passed over. The major forbs were silverleaf nightshade and western ragweed with redstem filaree and Croton spps. including Texas croton (C. texensis). In the first photograph herbaceous vegetation in the lighter green (yellowish-green) patch in the foreground was a mixture of curly mesquite and buffalograss, the former of which had somewhat greater cover. Darker green herbaceous layer in background was a "duke's mixture" of sideoats grama, Texas wintergrass, silver bluestem, dropseeds, plains lovegrass, hairy and red grama, and purple threeawn. Little bluestem was the least abundant grass followed by naturalized King Ranch bluestem. There were also individuals of Mediterranean annual bromegrasses, probably both cheatgrass and Japonese brome, in the interspaces among the mid-height bunchgrasses. The second photograph also displayed the patchy arrangement or structure of the shortgrass and midgrass components, perhaps more graphically than the contrasts shown in the first potograph. Frequently there are local grass communities (small-scale mixed species groups on microsites) on Edwards Plateau mixed prairie that include numerous grass species of various heights at maturity, but the more common organization is presence of tall-, mid-, and shortgrass species as segregated vegetational units (eg. a patch of curly mesquite and buffalograss; a separate local assemblage of sideoats grama, silver bluestem, and plains lovergrass). In foreground of second slide a patch of midgrasses included sideoats grama, perennial dropseeds, plains lovegrass, and common windmillgrass. In left midground there was a patch of curly mesquite and buffalograss similar to that in foreground of the first of these two slides. It seemed likely that the patch-by-patch arrangement or architecture of range plant communities on Edwards Plateau mixed prairie savanna reflected competition (eg. for light), adaptation to microsite variables (eg. edaphic features such as soil depth or stoniness), past spot grazing (perhaps localized overuse or overgrazing), or simply chance (ie. the Gleasonian view of plant communities). The second slide also illustrated selective "browsing" (defoliation) by fire. The larger mesquite at far right lost some lower limbs to the prescribed fire, but otherwise the existing shoot (tree above ground) survived because meristematic tissue was high enough above flames to avoid the thermal death point (usually regarded as 140 degrees Fahrenheit or 60 degrees Centigrade). By comparison, the smaller mesquite in center foreground was totally topkilled and had resprouted prolifically from the vast root system so typical of this species. This is a good example of the hard-learned fact that sometimes a larger, single-stemed mesquite has less foliar cover and shades less ground (thus perhaps causing less loss in forage production) than a smaller, multi-stemmed, shrubby mesquite. In such circumstances, a cool prescribed fire (as in a winter burn) that "flags" rather than topkills mesquite may be superior for brush control and general range improvement. This situation was further demonstrated in another photograph of this same range below (seven slides sebsequently). Other management and ecological perspectives must also be considered of course, including other brush species. On the range shown here the prescribed fire was needed primarily for reduction in cover and density of two Juniperus species as well as other miscellaneous brush plants like honey mesquite and tasajillo. Results of prescribed firing of this specific Edwards Plateau range were considered further below. Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

27. Representative samples of sward- Two photo-plots of the herbaceous layers of the oak-juniper mixed prairie savanna range introduced above. Peak standing crop of the herbaceous component of the range plant community on this grazed range nine months after a winter (January) prescribed burn. The first photograph was a composite sample of the herbaceous--mostly grass--component of this Edwards Plateau nine months after a wintr (January) prescribed burn. Grass species included curly mesquite, sideoats grama, buffalograss, hairy grama, red grama, and purple threeawn. Sward shown in the second photograph was dominated by plains lovegrass with sideoats grama, common windmillgrass, curly mesquite, Texas wintergrass, and hairy grama represented. Most common forb in both photo-quadrants was silverleaf nightshade. Texas croton and redstem filaree were also present. Photographs were taken at peak standing crop for herbaceous component of the range plant community in an extremely wet late summer-early autumn period (about six inches of rain in the four weeks immediately preceding photographs). Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

28. Patch of shortgrass sward- Photo-quadrant of a local microsite of oak-juniper mixed prairie savanna consisting of two shortgrass species: 1) buffalograss, shorter plants in foreground and 2) curly mesquite, somewhat taller plants in background. This sample of one herbaceous layer of this range vegetation represented a microenvironment that in the concept of Landscape Ecology was a localized patch in the overall matrix of shrub and tree-mixed (tall-, mid-, and shortgrass species) prairie. This layer of native vegetation was photographed on a range that had been burned by prescription nine months previously, grazed during the plant-growing season, and recieved about six inches of rain in the immediately preceding four weeks. Warm-season grasses and range vegetation overall was at peak standing crop and seed-ripe to seed-shatter stages. Sward is the term applied to the layer(s) of herbaceous plants, especially of grasslands and savannahs. Sward refers to both above- and belowground parts or zones. Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

29. Stewart stand-by of the Texas plains and plateaus- Sward of curly mesquite on the same range that had been treated by a cool winter (January) prescription burn nine months previously and that was featured in this series of slides. Curly mesquite is one of the major shortgrass species of the Southern Great Plains (of which physiographic province the Edwards Plateau is a section). Hitchcock and Chase (1950, p. 485) stated matter-of-factly: "Curly mesquite is the dominant 'short grass' of the Texas plains". These revered agrostologists were not specific as to the ecological status of curly mesquite as "the dominant". The consensus of scientific authority and the traditional interpretation of this species on most range sites has been that it becomes a major or dominant species under natural disturbances like drought or mismanagement of ranges, especially overgrazing. The Soil Conservation Service range site descriptions have almost invariably classified curly mesquite as an increaser or invader, again depending on range site. This conclusion was aptly stated in the Phillips Petroleum Company (1963, p. 43) booklet: "Curlymesquite has increased and invaded ranges where better grasses were killed out by abusive grazing". In revision of this work by Nicholson (Fort Hays State University, 2006, p. 49) specified: "This grass persists under heavy grazing but can be killed out by excessive grazing". It seemed that generally speaking curly mesquite fit the definition of an increaser, but as with other species ecological status varies by range site (ie. is range site-specific). Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October, peak standing crop.

30. Curly mesquite (Hilaria belangeri)- This stoloniferous sod-former is typically one of two major shortgrass species on mixed prairie savanna ranges in the Edwards Plateau. Buffalograss is the other--and often--codominant shortgrass. Both of these species are better adapted to "heavier" (more clayey) soils. They increase with heavy grazing and protracted drought (before they in turn are displaced by less palatable invader and, often, deeper-rooted species). Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October, peak standing crop and grain-shatter phenological stage.

31. What blessings prescribed fire hath wrought- A relatively cool prescribed burn in winter (January) topkilled most woody plants on this live oak-juniper mixed prairie savanna range in the central Edwards Plateau. Larger trees of plateau live oak and honey mesquite were either unaffected or minimally affected (eg. lost only lowermost limbs or buds). An example of this selective defoliation of fire on mesquite was presented previously (seventh slide preceding these photographs) in a description of this range type. In these two slides dramatic impacts of a winter prescribed burn were presented in regards to fire as a management tool to preserve Edwards Plateau savanna range by control and/or prevention of invasion by native woody plants that otherwise would proliferate to unnaturally excessive cover and density so as to become noxious range shrubs or trees (ie. brush). Prescribed fire is human manipulation of what is one of Nature's own forms of brush control. In fact, with possible exception of graqzing/browsing, fire is probably the most important and widespread natural phenomenon functioning to retard development of natural grassland and savanna vegetation toward dominance by trees and shrubs (ie. Mother Nautre's own choice for woody plant management). In the first of these two slides several mesquites of shrub form and size were topkilled by fire and sprouted profusely over the nine months following the prescribed burn. Conversely, two larger mesquites of small tree-size and shape (single trunk) shown in this photograph were less impacted by the prescribed fire (one mesquite at far right midground in front of topkilled mesquite scrub; another mesquite tree in center background). Various grass species that were generally identifiable in this first photograph based on color, shape, and/or size were abundant at peak standing crop and following abundant rains in the late summer-early autumn seasons. The perennial broadleaf herb, silverleaf nightshade, was conspicuous in the herbaceous understorey of this fired range. Silverleaf nightshade was the most common forb at this season. Many beautifully torched and scourched cedars were visible in the background. The second of these slides included topkilled or completely dead (wishful thiking perhaps) individual plants of tasajillo cactus (large, multistemmed shrub in left center), agarito (far left foreground, resprouting), two redberry or Pinchot juniper (both resprouting), and, arched around and framing the foremost juniper, honey mesquite. Grasses in the understorey included plains lovegrass, Texas wintergrass, curly mesquite, buffalograss, sideoats grama, purple threeawn, and silver bluestem. At far left background was a small stand of juniper and mesquite that had been missed by the prescribed fire. Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

32. Pals on an Edwards Plateau range- Growth of range plant species nine or ten months after a cool winter (January) prescribed burn on an Edwards Plateau live oak-juniper-mixed prairie savanna. Sideoats grama, State Grass of Texas, (center, taller grass) was accompanied by curly mesquite (immediate left foreground) and, in front and slightly to right-of-center of sideoats grama, cow-crippler or Devil's head cactus (Echinocactus texensis). All warm-season grasses on this range had apparently benefitted from the prescribed burn while cool-season grasses and forbs appeared to have been mostly, if not wholly, uninfluenced by the cool fire. As shown immediately above and below this photograph most woody plants except large live oak and mesquite were either topkilled or completely killed by prescirbed burning. Flames of the fire passed over the cow-crippler cactus before the heat from flames reached the thermal death point (usually a temperature of about 60° Celsius or 140 ° Fahrenheit)). Unlike most other shrubs on this range, the shoot of this cow-crippler cactus survived the prescribed fire. Wind-blown racemes of sideoats grama illustrated the phenomenon of anemochory (= aerochory), wind dispersal of plant propagules (pollen and spikelets in case of this grass species). Texas A&M University Sonora Experiment Station, Edwards County (pasture 8 Southeast), Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

33. Two paired comparisons of response to fire- One blueberry, post, or Ashe juniper and one redberry or Pinchot juniper were shown side-by-side in two locations to provide a "replicated" comparison of the two species' different responses to fire. In both "replications" redberry or Pinchot cedar had resprouted while blueberry or Ashe cedar had not resprouted but instead had been killed (totally dead, both shoot and root). Responses of both plants of both species was the usual or typical species-specific response. Redberry juniper is one of the few coniferous trees in North America that has capacity for coppicing or sprouting (resprouting from stumps, rootcrowns, or other meristematic tissue). In the first slide blueberry cedar was on the left and redberry juniper on the right; in second slide blueberry juniper was to the right while redberry cedar was to the left. On both comparison plots herbaceous species (mostly mid- and shortgrasses; main forbs were silverleaf nightshade and Texas croton) had obviously benefitted from the prescribed burn. Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

34. Setback- At least the prescribed winter (January) burn done nine months prior to these two shots topkilled these two redberry or Pinchot junipers. Both plants had sprouted from the bulbous lignotuber that is an obvious natural selection adaptation of this species to severe defoliation such as that by fire.Unfortunately, these two individual plants were not completely killed. They were severely injured and aboveground (shoot) growth of a considerable number of yedars (growing seasons) was killed. The second photograph showed details of stump sprouting or coppicing from the belowground (right below land surface) lignotuber present in this sprouting gymnosperm. With repeated prescribed burning Pinchot cedar can be controlled and topgrowth (growth and development of shoot) held to that many season's of growth. Repeated prescribed burning could be scheduled frequently enough to prevent seed formation and dispersal of this resprouting conifer. It was also obvious that herbaceous species (short- and midgrasses, silverleaf nightshade) were not severely damaged-- if at all--by prescription burning. Major grasses and forbs were perennials, but there were seedlings of Mediterranean annual grasses (mostly Bromus japonicus and/or B. tectorum) as well as redstem filaree or stork's bill in the green vegetation of this fired range which had been grazed during the previous growing season. Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna). SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

35. A survival characteristic of a range plant and an unfortunate feature for brush-fighting rangemen- Redberry juniper readily resprouts from meristematic tissue at both basal parts of trunk (stump) and higher parts of trunk and limbs/branches. Such meristematic tissue would probably be described as lateral meristems or, perhaps, intercalary meristems.This evolved survival adaptation to fire was all too evident in redberry cedar that had resprouted profusely over course of nine months following a prescribed burn in January. Shown in these two photographs were examples of branching or resprouting from lateral meristems on branches of redberry cedar on the same Edwards Plateau mixed prairier-live oak-cedar savanna range that was featured immediately above. Second slide presented details of branch sprouting. While prescribed burning appeared to be essential for maintenance of the herbaceous components (layers) of Edwards Plateau vegetation--indeed, of various Edwards Plateau range ecosystems and the natural landscape--such range fires are selective so as to greatly reduce if not eliminate the nonsprouting Ashe or post cedar shifting the competitive advantage to Pinchot or redberry cedar. Continued use of prescribed fire, that is necessary for preservation or restoration of native Edwards Plateau range vegetation, unfortunately results in greater absolute and relative cover of redberry juniper. Such phenomenon was readily apparent on this specific range, and there was no readily solution for this shift in species other than more expensive mechanical and chemical brush control practices. Ironically it is Ashe juniper that is the more palatable (mostly to deer and goats) of these two species. As such biological control by ungulates seemed of limited application. Texas A&M University Sonora Experiment Station (pasture 8 Southeast), Edwards County, Texas. October.

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36. Edwards Plateau range as the Tonkawa and, later, Lipan-Apache knew it-Two exterior or ecosystem-scale views of climax (or near climax) plateau live oak-mixed prairie savanna of the central, semiarid Edwards Plateau. This range had been completely--or nearly so--restored to botanical composition and structure of pre-Columbian, potential natural vegetation (as best estimated by vegetation scientists.). Range improvement practices consisted of intensive individual plant treatment of noxious woody species (= brush) like post or Ashe juniper, redberry or Pinchot juniper, honey mesquite, pricklypear, tasajillo, agarito, Texas persimmon, soapweed yucca, and whitebrush in conjuction with proper grazing management. Brush control by mechanical (primarily bulldozer and hand tools) methods with local burning, and with minimum soil disturbance, coupled with deferment of grazing and subsequent light stocking rate permitted range restoration to the virgin vegetation or perhaps to seral stage just below climax. Some range scientists might conclude that for pristine vegetation on this range site (Low Stony Hills, East) there should have been relatively more than the small cover of such decreasers as little bluestem, Indiangrass, Canada wildrye, and even rare representatives of big bluestem .This rangeman did not share that interpretation for this particular range environment (ie. this combination of edaphic, climatic, topographic features). High cover, density, and biomass--both absoultely and relatively--of sideoats grama, plains lovegrass, sideoats grama, green sprangletop, Texas cupgrass, silver bluestem, and cane bluestem, along with the proportions of little bluestem and Indiangrass plus the species diversity of such other native grasses as curly mesquite, buffalograss, Texas wintergrass, and tall dropseed (Sporobolus asper) along with species of large, native perennial forbs including copper or narrowleaf globemallow (Sphaeralcea angustifolia) and orange daisy (Zexmenia hispida= Wedeelia hispida) clearly showed this to be a superb example of semiarid Edwrds Plateau savanna. Other increaser or invader grasses included other perennial dropseeds, common windmillgrass, hairy and red gramas, and purple threeawn. Mini-editorial (author's opinion)- This range student disagreed with range site descriptions (Soil Conservation Service) and ecological site descriptions (Natural Resources Conservation Service) as to relative importance of tall grass species, especially big bluestem and Indiangrass, in climax range vegetation of central and western portions of the Texas Edwards Plateau. In this author's view, parts of some of these site descriptions made the potential natural vegetation on shallow sites of the Edwards Plateau (eg. Low Stoney Hills, Adobe Hills) sound more like humid or subhumid Flint Hills tallgrass prairie than semiarid mixed prairie savanna. These semiarid grass-shrub savanna rangelands probably have a closer affinity structurally and floristically with arid semidesert grasslands that are in closer proximity to the Stockton Plateau and/or Chihuhuan Desert than they do with the tallgrass prairies, Cross Timbers, and post oak savannas to the east and north. Examples of this include many of the rangelands (range types) of the western Edwards Plateau as in much of Sutton, Edwards, and Kinny Counties, Texas. This rangeman felt that the brief and generic description of native range vegetation of the central and western Edwards Plateau by Riskind and Diamond in Amos and Gehlbach (1988, ps. 13-14) was much more accurate and realistic (even though abbreviated) than the rather elaborate site descrptions by the SCS/NRCS in regards to relative cover and dominance of tallgrasses on shallow soils in semiarid precipitation zones. Description of the general Edwards Plateau savanna range plant community in the Juniper-Oak (SRM 733) rangeland cover type (Shiflet, 1994) was also more realistic, but it did not distinguish between eastern subhumid (mesic) and western semiarid (xeric) portions of the "Hill Country". There is considerable variation in average precipitation in the east to west extent of range types (and even in range sites) across the Edwards Plateau. Climatic atlases and other references typically show four or five four-inch increment isohytes over the east to west expanse of the Edwards Plateau (eg. Bomar, 1983, ps. 55, 57). Dominant woody species on the range presented here was plateau live oak, but judicuous brush control permitted scattered individuals of Ashe and redberry juniper, honey mesquite, agarito, Texas persimmon, and whitebrush. Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna) and SRM 733 (Juniper-Oak).. Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Low Stony Hills (East) range site. Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

37. Composition and structure of semiarid live oak-mixed praire Edwards Plateau savanna- Two views at scale of range plant community showing architecture and species make-up of mixed prairie. There were distinctive vegetational layers of tall-, mid-, and short grass species with plateau live oak (the dominant woody plant) along with juniper and mesquite (associate woody species) that comprised a savanna in the semiarid section of Texas Edwards Plateau. Dominant species of the shortgrass layer were curly mesquite and buffalograss with hairy and red gramas being local associate shortgrasses. Major midgrass species included silver bluestem, plains lovegrass, sideoats grama, Texas cupgrass, and Texas wintergrass or Texas speargrass. Green sprangletop, represented by individuals exceeding a yard in height, was also a major--sometimes a local-- dominant species. Distinction between midgrass and tallgrass is often arbitrary for such species as green sprangletop and Texas cupgrass, both of which were common on this range and reached the same height at maturity as the associated little bluestem. Canada or nodding wildrye was locally abundant beneath live oats where this cool season grass was associated with Texas wintergrass. The dominant plant species on this range that is always designated as a tallgrass was little bluestem. Little bluestem was followed in general abundance by tall dropseed with Indiangrass an occasional species while Johnsongrass was present as incidental plants. Less common grasses or those having less relative cover included common windmillgrass and purple threeawn. The most abundant forbs were two native perennials: copper or narrowleaf globemallow and orange daisy or orange zexmenia. Western ragweed was locally abundant, sometimes forming small exclusive stands. These ragweed stands or colonies had developed on soil laid bare by mechanical brush control (see below) and were not typical of undisturbed range vegetation. Naturalized Mediterranean herbs included annual bromes ( seedlings present likely included both cheatgrass and Japanese chess) plus redstem filaree or strork's bill. These were infrequent, but it was early autumn and there may have been later germination/emergence of these annuals. Mechanical treatment (bulldozer) of individual plants resulted in reduction in density and cover of both redberry and blueberry juniper and honey mesquite along with associated Texas persimmon. Smaller plants and a few larger individuals of these species remained along with those of agarito, whitebrush, soapweed yucca, pricklypear, and tasajillo. Edwards County, Texas. October, autumnal aspect. Peak standing crop of warm season species and range vegetation overall. Phenology of grasses varied from grain-ripe to grain-shatter stages in sideoats grama, silver bluestem, green sprangletop, and plains lovegrass; soft to mid-dough stage in Texas cupgrass and little bluestem; greenup of Texas wintergrass; and early seedling stage in annual Eurasian species. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna) and SRM 733 (Juniper-Oak).. Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Low Stony Hills (East) range site. Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

38. Samples of Edwards Plateau mixed prairie sward- Composition and structure of herbaceous layers of Edwards Plaeau live oak-mixed prairie savanna was portrayed in these two photographs. Two conspicuous herb layers were visible in both of these slides. Grasses readily discernable in the first photograph included plains lovegrass, silver bluestem, and Johnsongrass. The conspicous forb was western ragweed, an invader. This local microhabitat (= microsite) had been mechanically disturbed and plant species of the three successional statuses of decreaser, increaser, and invader were present in this one small photo-plot. Herbaceous range vegetation in the second slide was on an apparently undisturbed microenvironment. Major grasses included green sprangletop (which on this habitat achieved a mature height equal to that of little bluestem), sideoats grama, Texas cupgrass, and plains lovegrass. Hairy grama was the only common shortgrass species on this photo-quadrant. Therefore, this "plot" was predominantly a midgrass layer (stand of midgrasses). Such local stands of vegetation that were composed of most plants having similar heights were common. This general result was small-sized patches of various plant species arranged as "spots" of short-, mid-, and tallgrasses. Often range forbs were associated with grass species of similar or corresponding relative mature heights (eg. copper globemallow associated with plains lovegrass and green sprangletop). In this pattern, mixed paraire consisted of patches of range plant stands each of which tended to be dominated by either short-, mid, or tallgrass species rather than as a more uniform sward in which tall-, mid-, and shortgrasses were in almost all local groups of range plants. The herbaceous patchwork pattern was a more common arrangement. Diversity consisted of numerous patches differing in botantical make-up and not of a fairly uniform, diverse mix of plant species throughout the plant community (across the range). Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna) and SRM 733 (Juniper-Oak).. Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Low Stony Hills (East) range site. Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

39. Some more samples of Edwards Plateau mixed prairie sward- Diversity in range compostion of herbaceous plants was presented in two photo-quadrants on semiarid mixed prairie an Excellent range condition class. These samples of range vegetation were on the same range as featured in the preceding six (two sets of three) slides. Obvious species present in this range plant community as shown in the first slide included green sprangletop, Texas wintergrass (large bunchgrass behind and slightly to left of prominent green sprangletop), sideoats grama, common windmillgrass (far-right, rear margin), and copper globemallow (the conspicuous forb) in background. In the second slide copper or narrowleaf globemallow opverwhelmed the stage while sideoats grama followed by green sprangletop played graminaceous escort. A "rogue" leaf of alien Johnsongrass in left foreground served as a size reference for leaves of copper globemallow. Edwards County, Texas. October, autumnal aspect. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna) and SRM 733 (Juniper-Oak).. Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Range site: Low Stony Hills (East). Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

40. Plains lovegrass (Eragrostis intermedia)- Hearty specimens of a dominant climax (decreaser) grass on the semiarid Texas Edwards Plateau mixed prairie-shrub savanna. Like the more common and, often, associated sideoats grama, the successional status of plains lovegrass varies widely depending on range type and range site. On harsher habitats such as in the semiarid zone, on shallow soils, and south or west slopes of the Edwards Plateau plains lovegrass is a decreaser. On more mesic range sites in the eastern Edwards Plateau this species responds more like an increaser. Plains lovegrass is often a major forage producer that yields comparatively large quantities of palatable, nutritious herbage. It has been widely used in reseeding former cropland in the Great Plains, especially as a component of species mixtures for land in the Conservative Reserve Program. This bunchgrass typically has considerable capacity for asexual reproduction via tillering. Plains lovegrass is also a good producer of viable grain so that this widespread native grass also reproduces sexually. Given its palatablity, potential for high yield under semiaridity, successional status, ease of establishment, and geographic range plains lovegrass is usually regarded as the single most important Eragrostis species on North American ranges. These plants were on the same Edwards Plateau live oak-mixed prairie savanna range as presented in the immediately preceding four sets of photographs. Edwards County, Texas. October, seed-ripe stage.

41. Pains lovegrass from closer views-Many of the Eragrostis species have a general shoot morphology consisting of a basal tuft of leaves from which arise proportionally long culms that terminate in some of the longest panicles of any grasses of comparable size. The first of these two slides presented an individual of plains lovegrass displaying the disproportionately lengthy and generally large panicle of this species. The second of these slides presented the typical tuft of leaves at base of this same plains lovegrass plant. This individual was growing on the near-climax Edwards Plateau live oak-mixed prairie range that was featured immediately above. Edwards County, Texas. October, peak standing crop at seed-ripe stage.

42. Inflorescence of plains lovegrass- Detailed views of the upper culm and panicle of plains lovegrass presented to shown key characteristic of this major species of Edwards Plateau ranges. The first photograph showed flag leaf subtending the panicle and base of panicle and rachis. One of the most distinguishable key identifying features of plains lovegrass is the numerous tufts of pilose or silky hairs in some upper leaf axils and and at points along the panicle rachis. This characteristic was presented in this slide. Second photograph showed the much-branched panicle with a characteristic sparse number of spikelets. This was the same individual plant featured in the immediately preceding set of two photographs. Edwards County, Texas. October, grain-ripe phenological stage.

43. Part of a panicle of plains lovegrass- Photograph showing a section of the spreading panicle of plains lovegrass revealing the potential of this species to "set seed" when growing--especially soil moisture--conditions are favorable. Edwards County, Texas. October, hard-dough to grain-ripe stage.

44. Spikelets of plains lovegrass- Portion of panicle of the plains lovegrass plant shown in preceding slides presenting the arrangement of spikelets which are fewer-flowered (generally 3 to 8 or 10 florets per spikelet) than many, probably most, Eragrostis species. Edwards County, Texas. October, grain-ripe stage of phenological development.

45. Closer look at plains lovegrass spikelets- Several spikelets of plains lovegrass were shown for greater detail and clarity of these fundamental units of the grass inflorescence. Lovegrasses (Eragrostis spp.) have some of the smallest grains and spikelets among the North American Gramineae. Edwards County, Texas. October, hard-dough to grain-ripe stage.

46. Texas cupgrass (Eriochloa serecia)- Large individual of Texas cupgrass growing among Texas wintergrass, sideoats grama, and green sprangletop on the near-climax Edwards Plateau live oak-mixed prairie savanna range introduced above. Texas cupgrass is an extremely palatable, native panicoid grass that is rapidly grazed out under excessive stocking, especially of cattle or horses. This species is generally interpreted as a decreaser though, of course, disturbance responses are range site-specific. On various range sites in the Edwards Plateau as well as adjoining portions of the Rio Grand Plains Texas cupgrass is typically associated with green sprangletop, plains lovegrass, sideoats grama, and Texas wintergrass. Texas cupgrass is a densely tufted bunchgrass with asexual reproduction limited to tillering.. This individual exceeded two and a half feet in height and was growing beneath the crown of a plateau live oak. Photographs of panicles of this particular plant were presented immediately below. Edwards County, Texas. October, soft to mid-dough stage of phenology. Low Stony Hills (East) range site.

47. Inflorescence of Texas cupgrass- Set of three photographs to show the arrangement and details of spikelets in the contracted panicle of this panicoid grass. In this species, spikelets are arranged along unbranched primary branches that lie closely --almost adnate--to the central axis of the panicle (Gould, 1975, p. 433). Hitchcock and Chase (1950, p. 588-589) interpreted the inflorescence of Texas cupgrass as consisting of racemes along a rachis. The interpretation by Gould (1975, p. 433) was consistent with recognition of six subfamilies of Gramineae and more phylogentically precise than the more artificial approach of only two broad subfamilies used by Hitchcock and Chase (1950). The unique floral feature of this species is the small indentation or depressed portion of the branch in which the caryopsis is situated, hence the common name of cupgrass (ie. depression in which the grain lies is a "cup"). Inflorescences on the individual specimen shown immediately above. Edwards County, Texas. October, soft to-mid dough phenological stage.

48. Green sprangletop (Leptochloa dubia)- Large single plant of green sprangletop with several sexual (floral) culms plus several inflorescences (right foreground) of a second plant that was "off-stage". On shallow, rocky range sites in semiarid parts of the Edwards Plateau green sprangletop is usually regarded as a decreaser as it typically declines rather quickly on such harsh sites with heavy grazing (and, of course, overgrazing). Green sprangletop grows in association with sideoats grama, Texas cupgrass, Texas wintergrass, and silver bluestem or pinhole bluestem on mixed prairie savanna rangeland in the semiarid Edwards Plateau. Green sprangletop can grow to mature heights exceeding three feet. The individual shown in this photograph reached two and a half feet and thus was an example of the habit and size of the larger form of this species. Other individuals of green sprangletop are considerably shorter and smaller overall, especially under heavier grazing. This example was growing on the Excellent condition Edwards Plateau live oak-mixed prairie savanna range described above. On many range sites, including some sites of semidesert grassland, green sprangletop is regarded as an increaser. On various of the shallower, more xeric range sites in the semiarid Edwards Plateau green sprangletop has a response more like that of a decreaser. Gould (1975, p. 226) described this eragrostoid grass as being strictly cespitose with neither stolons nor rhizomes, buth Hatch and Pluhar, 1993, p.99) ascribed rhizomes to green sprangletop and Silveus (1933, p. 368) implied the same. Edwards County, Texas. October, immediate post-peak standing crop at grain-shatter phenological stage.

49. Inflorescence of green sprangletop- An inflorescence on the large individual green sprangletop featured in the preceding photograph. The common name of sprangletop refers to the spreading--hence, "sprangled"--arrangement of the inflorescence. Generically speaking the inflorescence of this member of the Eragrostoideae subfamily consist of numerous racemes on primary branches directly off of the rachis. Edwards County, Texas. October, grain-ripe to grain-shatter stage.

50. Young flowering shoots and inflorescences of green sprangletop- Late summer shoots of green sprangletop that developed following soaking rains after a severe summer drought These late-season shoots were either stunted (or would appear as such) because there was not enough growing season remaining to permit development to normal mature size of sexually reproductive shoots in this species. Photoperiod was certainly a major factor in this regard, though the phenomena of photoperiod interacted with drought stress. Green sprangletop produces cleistogomous spikelets enveloped within sheaths of basal leaves (ie. in effect, still in the boot). Cleistogamy is the condition in which flowers do not open normally so that any fruit produced is through self-pollination and self-fertilization. Cleistogamy existed in green sprangletop shoots shown in both of these two photographs. A clone, clonal unit, or ramet of one (the same) green sprangletop plant was shown in each of these slides. On each clone there were very short shoots that remained encased within a folded sheath and unopened blade of a single leaf (ie. the boot). These were present at the base and in front of the more obvious stunted shoot that was bearing an emergent inflorescence. Within the boots of these extremely short shoots there were "hidden"-- meaning unexerted-- inflorescences. Again, these shortest shoots were in front of both stunted shoots that bore newly emergening or exerted inflorescences (one shoot with an opening inflorescence in each of these slides). These "hidden" inflorescences were retained within the boot and these unopened racemes were bearing cleistogomous spikelets. The tips of these cryptic inflorescences were barely visible (appearing as pubescence) from tip of the boot (= folded leaf). Erath County, Texas. Understorey of Western Cross Timbers. September. Again, two forms of the flowering stage of phenological development: 1) inflorescence emerging from the boot and 2) nonemergent or unexerted inflorescence (retained within the boot) bearing cleistogamous flowers.

51. Anthesis in green sprangletop- The distal portion of a green sprangletop inflorescence, the racemes--with young florets and their exerted anthers--of which were spreading or extending away from the rachis. This stage of floral development was a day or two advanced beyond emergence of the inflorescence from the boots on separate shoots as presented in the two slides immediately above. Erath County, Texas. Understorey of Western Cross Timbers. September, anthesis.

52. Champion of its kind- An exceptionally large individual of silver bluestem at peak standing crop on a nearly pristine range of climax live oak-juniper-mixed prairie savanna in Edwards Plateau. Silver bluestem and the closely related cane bluestem are widespread dominant midgrass species of the Edwards Plateau. Response of silver bluestem to grazing on Edwards Plateau ranges is very much range site-specific varying from decreaser to increaser and, perhaps on some of the more mesic sites, even an invader. Range site potential varies tremendously across the east-to-west precipitation gradients of the Edwards Plateau vegetational (land resource) area that extends from the Blackland Prairie on the east to the Trans-Pecos Basin and Range Region on the west (ie. the Stockton Plateau portion of the Edwards Plateau). Generally speaking, silver bluestem is an increaser over most of its species range, but on extremely harsh sites of the western Edwards Plateau this midgrass responds as a decreaser. Conversely, on more favorable and productive range sites on which climax range vegetation is dominated by tallgrass species (eg. eastern parts of Edwards Plateau closer to Cross Timbers and Blackland Prairies vegetational areas) silver bluestem can be an invader (although it has traditionally been classified as an increaser on most range sites). Texas A&M University Sonora Experiment Station, Edwards County, Texas. October,

53. Partly in and out of the boot- The four apices of silver bluestem shoots in these two photographs presented four degrees of emergence of the inflorescence (panicle) from the boot. Panicle atop the left shoot in second photograph was fully emerged or exerted. Details of fully expressed panicles were shown in the next set of two slides. West Cross Timbers near end of a summer of severe drought. Erath County, Texas. September, emergence of inflorescence from boot.

54. Silvery spectacle- No, not necessarily spectacular but a conspicuous spectacle nonetheless was this appearance of showy inflorescences of silver bluestem in the Western Cross Timbers. Terminology applied to inflorescences of Andropogon, Bothriochloa, Schizachyrium, and Dichanthium species has about as many interpretations as does taxonomy of these taxa. Contemorary description of this inflorescence type is panicle with primary racemose branches (Gould 1975, p. 591; Hignight et al., 1988, ps. 8, 23; Hatch and Pluhar, 1993, p.43). These specimens were growing in the West Cross Timbers near end of a long, hot sumer of severe drought and following two mowings. This species is survivor if given half a chance (come to think of, even if not given half a chance). Erath County, Texas.September, fully emerged inflorescence, at 1) pre-anthesis stage (first photograph) and 2) early dough stage (second photograph).

55. Stand of copper or narrowleaf globemallow in semiarid Edwards Plateau - Local population of copper globemallow on a plateau live oak-mixed prairie savanna at or approaching state of climax range vegetation.This was the dominant forb in this range plant community. These plants were part of the vegetation on the pasture in Excellent range condition class range (Low Stony Hills, East, range site) featured above. Associated herbaaceous species growing adjacent (or in close proximity) to this stand of forbs included Texas wintergrass, plains lovegrass, green sprangletop, Texas cupgrass, and sideoats grama. Edwards County, Texas. October: autumnal aspect of vegetation with globemallow at peak standing crop and full-bloom stage of phenological development..

56. Copper or narrowleaf globemallow (Sphaeralcea angustifolia)- Various Sphaeralcea species are frequently the dominant or, at least, a major climax forb on ranges in the semiarid region and, sometimes locally, in desert vegetation of the more westward arid region. Some of these various kinds of globemallow were featured in Range Types of North America. These comprised the most abundant (had the greatest cover and density) forb on the Edwards Plateau live oak-mixed prairie savanna range that was at or approaching state of climax range vegetation featured in this section of the Edwards Plateau chapter. Most Sphaeralcea species are quite palatable (often highly preferred) by small ruminants like sheep and deer. Globemallows are usually decreasers. On some range sites the goobemallow species respond as decreasers even under grazing by cattle. Presence of copper globemallow on the featured plateau live oak-mixed prairie savanna range in Excellent condition class range attested to the pristine-like nature of this semiarid native grazing land. Copper globemallow was a striking beacon for the devotion and management shown by this landowner, the fruits of whose outstanding stewardship were enjoyed by those who saw it. The key (and foolproof) characteristic of members of the Malvaceae is the prominent staminal column in the usually colorful inflorescence. Such was readily visible in the second of these two photographs. Edwards County, Texas. October. Peak standing crop and full-bloom stage of phenological development.

57. Orange daisy, hairy wedelia, or orange zexmenia (Zexmenia hispida= Wedelia hispidia)- This composite (tribe: Heliantheae) was the second most common "wild flower" on the Excellent condition Edwards Plateau live oak-mixed prairie savanna range featured here. This species has been variously described as a forb or suffrutescent (or suffruticose) shrub with most accurate designation obviously depending on degree of woodiness, which varies with factors including plant age, climate, genotype, phenotypic expression, range type, and range site. Orange zexmenia often grows to dimensions of four to six feet or more across with a height of over two feet. It is a favored species for nectar-feeding butterflies in late summer through autumn making it an ideal forb for enthusiasts who want native plants for their butterfly gardens. It is probably also palatable to forb- and browse-feeders like sheep, goats, and deer as evidenced by greater abundance of this composite on areas protected from improper grazing. Accessions of orange zexmenia were evaluated by the Kika de la Garza Plant Materials Center (1999) in Kingsville, Texas so that release of a selection of this valuable forb seemed likely. The small specimen (more of a forb than a shrub) presented here was used to show the typical habit of its species, but the small size (and perhaps young age) of this individual was not typical of the shrub "version" of this composite. Range plants associated with orange zexmenia on this range included sideoats grama, Texas cupgrass, Texas wintergrass, plains lovegrass, and curly mesquite. Edwards County, Texas. October, full-bloom stage of phenology.

58. Colorful gathering- An extremely large specimen of orange zexmenia or hairy wedelia had attracted an arrary of lepidopteran visitors. Orange daisy is one of the favorite "wild flowers" (forb or, in this instance, suffrutescent shrub) for numerous species of butterflies and moths: larvae feed on foliage and, as shown here, adults use nectar as a rich source of late summer-fall feed. Orange zexmenia is especially important as an energy source for migratory lepidoptera species like the monarch butterfly (Danaus plexippus). In turn, this phenomenon has begun to be another monetary flow for ranchmen who can collect egress fees and associated income from nature-lovers willing to pay for the opportunity to view the beauty of what ranchers heretofor saw merely as "bugs" and "weeds". Of course, butterflies like the ones shown here were range animals on the natural pastures of the Edwards Plateau long before exotics like beef cattle, sheep, and goats. Orange zexmenia is a native range plant that it is likely a climax species as well. Bloom on wild things. Val Verde County, Texas. October, peak standing crop and full-bloom stage.

59. Orange zexmenia, hairy wedelia, or orange daisy (Zexmenia hispida= Wedelia hispidia)- Details of orange zexmenia on semiarid Edwards Plateau live oak-juniper- mixed prairie savanna range. This is one of the most striking "wild flowers" throughout western portions of the Edwards Plateau and Rio Grande Plains, eastern parts of the Chihuhuan Desert, and transition zones thereof. Edwards County, Texas. October.

60. Slender greenthread (Thelesperma simplicifolium)- Another "damn yellow composite" (and member of Heliantheae tribe) that is a widespread "wild flower" throughout the Edwards Plateau. Unlike the preceding orange zexmenia, however, this species is clearly herbaceous and a range forb. Such vivid range plants with their short-lived, showy array of petals often appear to be much more abundant and have greater foliar cover than is actually the case. Nonetheless, they add biodiversity and visual beauty to range vegetation thereby attracting a wider following of range plant--especially native--enthusiasts. This would appear to be a great virtue for the Range Management fraternity (and related groups such as Native Plant Society or Society of American Foresters) which are thrashing madly about in all directions at once (and selling their Faustian souls) just to maintain their current memberships. Meanwhile, ecological role or "importance" of incidential range plant species like slender greenthread remain unknown. For that matter, economic importance remains pretty much a mystery. Asethetic values of "pretty flowers" can at times be translated directly into monetary terms as when landowners receive lucrative rewards from nontraditional consumers like bird- (or butterfly-) watchers. Edwards County, Texas. October, full-bloom stage.

61. Browse and mast of plateau live oak (Quercus virginiana var. fusiformis)- Two photographs used to emphasize that fruit (acorns), leaves, and twigs of this evergreen white oak (Leucobalunus subgenus) provide invaluable feed for many range animal species (birds, rodents, ungulates, insects, and, formerly, even humans). Live oak is widely distributed throughout southern portions of North America, but it is a dominant tree and/or shrub throughout almost the entire extent of Texas Edwards Plateau. Arguably, live oak was the major or most important dominant woody plant with juniper and honey mesquite as associate woody species in pre-Columbian vegetation over much of the Edwards Plateau and adjoining grasslands to the east. Live oak was the only dominant of the two major rangeland cover types named and described for the Edwards Plateau by the Society for Range Management (Shiftlet, 1994): 1) Juniper-Oak (733) and 2) Mesquite-Oak (734). This was consistent with the "units of vegetation" or "physiogonomic types" of Juniper-Oak Savanna and Mesquite-Oak Savanna proposed by Kuchler (1964, ps. 5, 86, 87) and later incorporated into Forest and Range Ecosystems (Garrison et al., 1977). The case can be made, therefore, that plateau live oak was the most widespread, general, or defining woody dominant or the Edwards Plateau. In absence of natural fires and with compounding phenomena from overgrazing, oil and gas development, tillage, and climatic changes all species of woody plants have increased across the entire Edwards Plateau with but few rare exceptions. Erath County, Texas. September, fruit-ripe/fruit shedding stage.

62. Close-up view of acorns and leaves of plateau live oak- Like many, probably most, oak species live oak sheds the nut portion of its acorn from the surrounding cup which is retained on the tree for considerably longer periods of time. Acorns of plateau live oak occur solitary or as single units, paired, or as units of three. All of these arrangements were present in this or two preceding photographs. There has been continuing controversy over taxonomy and nomenclature of the live oak taxon of the Edwards Plateau, Cross Timbers, and even Coastal Prairie and Marshes areas in Texas. Some authorities interpreted plateau or escarpment live oak as Quercus fusiformis whereas other treated it as Q. virginiana var. fusiformis (Correll and Johnston, 1979, p. 483; Diggs et al., 1999, p. 716). Authors in Amos and Gehlbach (1988) used Q. fusiformis in the definitive treatment of Edwards Plateau range vegetatiion. Conversely, other authors such as Miller and Caudle (in Shiflet, 1994) when describing the two major savanna rangeland types of the Edwards Plateau simply used the general designation of live oak (Q. virginiana). By whatever name, this is an extremely valuable and much beloved plant (until it reaches unnatural levels of cover and density thereby becoming a brush species). Live oak is characteristically very slow-growing. It has wood with a hardness, smoothness, and consequent beauty consistent with slow growth of the plant. Erath County, Texas. September.

63. Too much of a good thing- A live oak-mixed prairie savanna range in the Edwards Plateau that had been degraded by overgrazing. This range was converted into a buffalograss-purple threeawn ( Aristida purpurea complex) disturbance climax by improper grazing management (or, samething, improper husbandry of livestock that forced them to overuse the range over a prolonged period of time). Current species of livestock were beef cattle (brood cows and calves) and goats (Angora wethers). Grazing--specifically, the stocking and management--of more than one species of animal on a range is common use. Grazing of only two kinds of managed animals is dual use. Dual or common use is a rule-of -thumb a superior grazing management practice, especially on grazing lands having numerous plant species, because it permits more efficient (= less wasteful or more thorough) use of feed resources. This is particularily true when range vegetation consist of both woody and herbaceous plants and species of range animals include both grazers (grass and forb consumers) and browsers (browse-preferring herbivores) as, for example, cattle and goats, cattle and deer, horses and deer, etc. Stocking of cattle and goats along with native white-tail deer on this range with a potential natural plant community of tall-, mid-, and shortgrass species, numerous forbs, and various trees and shrubs (eg. plateau live oak, juniper, mesquite, agarito, pricklypear) was wise use management, a commendable combination of range animals for this Edwards Plateau mixed prairie savanna. The abuse of this range was stocking too many animal units (head) and/or for too long a period of time, at the improper season, or related mismanagement of livestock.Wildlife like deer had not been managed directly as had the tractable livestock. This native grazing ground with a potential natural (climax) vegetation comprised of numerous plant species (presented and discussed below) had been converted into a grazing disclimax mostly of buffalograss with scattered individuals of purple threeawn (and small patches of curly mesquite with invasion by seedlings and small saplings of honey mesquite and some agarito "for good measure". Present but with least cover and density was Texas wintergrass or Texas speargrass. For whatever reasons pricklypear was absent (for all practical purposes but give it time). Edwards County, Texas. October, autumn aspect. Peak standing crop of range plant community.

64. This land and these livestock deserve better- A live oak-mixed prairie savanna range mismanaged by overgrazing (currently by beef cattle and Angora goats) had been convrted into this grazing disclimax. Overgrazing is prolonged overuse that leads to a degraded or depleted range or pasture where degradation or depletion of native grazing land is defined as a stage of range plant community development resulting from (a reflection of) retrogression. Retrogression is the vegetation development process in which there is a series of plant community stages that departed from climax or ecologically desirable seral stages. Retrogression, a synonym of which is range degeneration, is the pattern of retrograde development from a successionally higher or more desirable range plant community to those community stages of lower successional status. Overuse is current or present utilization (defoliation) that exceeds proper use and that if continued for a long enough period of time (usually several plant-growing seasons) will result in overgrazing (ie. range retrogression, a degraded range). Overuse, and the prolonged practice of which is overgrazing, result from overstocking which is running or placing too many animals on the grazing unit and/or for too long a period of time that eventually will result in overuse and, if continued for long enough, in overgrazing deteriorated grazing land. Overuse (excessive current defoliation by grazing/browsing animals) and overstocking refer to the current growing season or grazing period (usually thought of as a year or the growing and/or grazing portion of a year). These terms were defined by standards of the profession as set forth by the Society for Range Management (Kothman, 1974; Jacoby, 1989). Sadly for this range and the livestock shown here (but for benefit of students) all of these terms were displayed here in action. This range had been subjected to overuse for many years. This stage of range depletion (= degradation retrogression) did not happen during the current or, even, last few years or plant-growing seasons. Lung cancer does not development overnight or from a few "sneaked smokes". Plant species present on this range were almost exclusively buffalograss with scattered individuals of purple threeawn and little patches of curly mesquite along with more numerous mesquite seedlings and small saplings and agarito. Least abundant was Texas wintergrass. The potential range plant community was displayed in the next two slides. The quality breeding and obvious gentle handling of these cows and the Angora wethers (the latter barely visible in background) had not been matched in stewardship of this rangeland. Edwards County, Texas. October, autumnal aspect (and peak standing crop of range vegetation).

65. What could (should) be- A readymade exclosure was afforded by this fencerow adjacent to the range of a buffalograss-honey mesquite grazing disclimax described in the preceding two photographs. Range vegetation next to the woven and barbed wire fence was dominated overwhelmingly by vine mesquite (Panicum obtusum). Various other herbaceous species (almost all perennial grasses) present included sand dropseed, green sprangletop, and sideoats grama (all three visible in immediate foreground), silver bluestem, Texas wintergrass, and Johnsongrass in that relative order and with sparse cover of buffalograss and curly mesquite. Major forb was western ragweed (Ambrosia psilostachya) with silverleaf nightshade (Solanum elaegnifolium) a distant second. There were no woody plants except honey mesquite which were growing up through the fence wire. Edwards County, Texas. October, autumnal aspect and peak standing crop of range vegetation.

66. A choice on Edwards Plateau rangeland- On the left, the overgrazed range that was almost exclusively buffalograss except for scattered individual cespitose plants of purple threeawn and Texas wintergrass, the latter of which was far more plentiful (actually, less restricted) close to the fence, along with seedlings and small saplings of honey mesquite and a few agarito. An interesting phenomenon apparent on this overgrazed range was absence of forbs. This contrasted sharply with abundant western rangeweed and a good bit of silverleaf nightshade just across the fence. Apparently, longterm grazing by Angora goats had resulted in eradication of both of these forb species from the buffalograss disclimax. Western ragweed is valuable for bobwhite quail (Colinus virginianus) and deer (Tyrl et al., 2002, p. 225) and, to lesser degree, so is silverleaf nightshade (Tyrl et al., 2002, p. 341). Students of Range Management (including the specialty of Range Economics) and Agricultural Economics should note that overgrazing like that shown here is never a profit-maximizing practice. That is an economic fact of life. At least it is economic reality as long as there is any cost associated with inputs which, in this case, was head (numbers) of livestock each of which had an opportunity cost of retained ownership. Gross mismanagaement of economic and natural resources like that showh here is most commonly for purposes of status grazing, overstocking in order that the livestock owner can brag about how many head of livestock he has. This owner likely had a big dually,diesel pick-up to go along with his sleek cows, and to haul hay and concentrate supplements to the cows come the first dry spell. He can show off the loud, flashy dually loaded with expensive boughten feed. Yep, a real stockman. Edwards County, Texas. October, autumnal aspect and peak standing crop of range vegetation.

67. More xeric form of semiarid Edwards Plateau mixed prairie-scrub savanna- At far western edge of the Edwards Plateau adjacent to the Stockton Plateau the grass-shrub savanna is composed primarily of more scattered individual plants of mid- and shortgrass species along with smaller, lower-growing shrubs. Plateau live oak is less common as this species approaches the driest extreme of its geographic range. Junipers continue to be dominant woody plants, but other shrubs share this dominance or, at least, are stronger associate species. Sideoats grama and green sprangletop remain dominant grasses, but in the climax range vegetation bluestems like silver bluestem and pinhole bluestem (Andropogon perforatus= Bothriochloa barbinodis var. perforatus) and Texas wintergrass are much less common (reduced cover and lower density) while smaller xeric grasses like red grama, curly mesquite, slim tridens (Tridens muticus), and various species of threeawn make up higher proportions of the herbaceous layers. The range shown in these two photographs was a relict area on which fire had eliminated most of the juniper (remaining dead shoot of Ashe juniper in center background of first photograph) while an amazing mixture of range plants thrived on a long southwest-facing slope. Rangeland shown here was on a catena or, more precisely, toposequence that was defined as "a sequence of related soils that differ, one from the other, primarily because of topography as a soil-formation factor" (Soil Science Scoeity of America, 2001). For instructive or management purposes this was one range site (Low Stony Hills, West). This range plant community was a classic savannah with a rich botanical mixture of both herbaceous and woody species almost all of which were listed as important members of the Juniper-Oak and/or Mesquite-Oak rangeland cover types (Shiftlet, 1994, ps. 108-109) that make up most of Edwards Plateau range vegetation. Major grasses included sideoats grama, the overall dominant, green sprangletop, the associate grass species, slim tridens, arrowfeather threeawn (Aristida purpurascens), hairy grama, red grama, and curly mesquite. Largest species of grass was silver bluestem, but it was present mostly at low density and cover and this primarily on deeper soil among rocks on more easterly facing slopes. The major forb was bluntleaf or spikeless spikemoss (Selaginella mutica). The most abundant woody species were all shurbs and included catclaw or catclaw mimosa (Mimosa biucifera= M. lindheimeri); Texas kidneywood (Eysenhardtia texana); orange zexmenia (clearly the shrub not forb form); some variety of Lindheimer's, Engelmann's, or Texas pricklypear (most likely the more eastern Opuntia engelmannii var. lindheimeri); Spanish dagger, Torrey yucca, or palma pita (Yucca treculeana= Y. torreyi), Ashe juniper, Texas persimmon (Diospyros texana) the larger green shrub at left margin of foreground, sotol (Dasyliron texanum), and beargrass or sacahuista (Nolina texana). Val Verde County, Texas. October: autumnal aspect; peak standing crop. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna) and SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Low Stony Hills (West) range site. Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

68. Mixed players but not missed opportunities- This photo-transect highlighted the botanical richness of a mixed prairie-shrub savanna range in advanced state of succession. This range was certainly in Excellent range condition class, but fire in recent past had probably reduced Ashe juniper to such extent that this range vegetation was probably sub-climax. On this range there were numerous range plant species occupying various microhabitats resulting in greater biodiversity than was the situation on more mesic (and generally more favorable) range environments in the Edwards Plateau. Said another way, the harsh environment of this shallow, semiarid range site provided a disproportionately high number of ecological niches. Major grasses on this phot-quadrant were (in order of relative cover) sideoats grama, green sprangletop, and slim tridens. Shrubs included catclaw mimosa, Texas kidneywood, sacahuista, sotol, Texas or Lindheimer's pricklypear, and Texas persimmon. Surface herbaceous layer was dominated by bluntleaf or anwless spikemoss (some was visible surrounding small rocks in center of photograph. Val Verde County, Texas. October: autumnal aspect; peak standing crop. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna) and SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Low Stony Hills (West) range site. Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

69. Not bad for a rocky, shallow slope in the semiarid zone- Two examples of range vegetation on a semiarid mixed prairie-shrub savannah. Major grasses were sideoats grama, green sprangletop, and slim tridens. Most abundant shrubs were catclaw mimosa, Texas kidneywood, and orange zexmenia with a species of pricklypear typically ever-present. Biomass and, thus, expression or portrayal of this range plant community, especially species composition of herbaceous layers, was exceptional due to extremely heavy and frequent rainfall during latter part of the growing season (for warm season species which made up most of the vegetation on this site). Val Verde County, Texas. October: autumnal aspect; peak standing crop. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna) and SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Low Stony Hills (West) range site. Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

70. Sparse but present- Two more photo-plots of range vegetation on a semiarid mixed prairie-shrub savanna on a southwest-facing slope. First of these two slides was a representative photo-plot on the primarily bare ground portion of this range site. The grass species visible on this sample of the range was sideoats grama, the dominant herb on this site. Awnless or bluntleaf spikemoss was the overall dominant forb on this range. Spikemoss made up a (the) surface layer of vascular range vegetation at this location. The second photo-quadrant was a representative composite of herbaceous layers of this Excellent condition semiarid mixed prairie-shrub savanna. Sideoats grama, green sprangletop, slim tridens, hairy grama, arrowfeather threeawn, an red grama were all present. Orange zexmenia of the suffrutescent (or suffruticose) form was the major shrub species. Principal forb was bluntleaf or awnless spikemoss, but on this microsite of slightly less shallow soil this vascular cryptogam was nowhere as plentiful as on the more bare microenvironment represented by the first of these two slides. Val Verde County, Texas. October: autumnal aspect; peak standing crop. FRES No. 32 (Texas Savanna Ecosystem). K-77 (Juniper-Oak Savanna) and SRM 733 (Juniper-Oak). Mixed Grass-Scrub Series 143.14 (Brown et al., 1998, p. 40). Low Stony Hills (West) range site. Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

71. Slim tridens (Tridens muticus)- The inflorescence of slim tridens was nterpreted as a short-branched, interrupted panicle (Hitchcock and Chase, 1950, p.216) and as an elongated, spikelike, contracted panicle (Gould, 1975, ps. 204, 213). In the Edwards Plateau slim tridens flowers in late summer to autumn. Silim tridens is a densely tufted bunchgrass that typically responds as an increaser on Edwards Plateau range sites. Val Verde County, Texas. October, grain-ripe stage.

72. Texas kidneywood (Eysenhardtia texana)- This woody papilionaceous legume is a shrub of intermediate height depending on growing conditions. The common name of kidneywood was derived from previous use of extracted products from other Eysenhardtia species as a medicine for treatment of kidney disease. Wood of E. texana was formerly used as a natural dye. The species emits a strong odor when plant leaves and young twogs are bruised. Kidneywood grows from the Edwards Plateau westward to the Chihuhuan Desert, but it is more abundant in the former. Scifres (1980, p. 110) remarked that this shrub is of variable palatability to livestock and wildlife, but that is a valuable browse plant and should be encouraged on ranges through judicious management resulting in light browsing. Readers desiring more general information or details concerning taxonomy and idntification on Texas kidneywood were advised to consult (Vines, 1960, p. 528) and Powell (1988, 209-210). Above photographs were taken from the range representing the Low Stony Hills, West range site featured above. Val Verde County, Texas. October, fully formed legumes with immature seeds.

73. Catclaw or Lindheimer (or Lindheimer's) mimosa (Mimosa biuncifera= M. lindheimeri)- This low-growing woody member of the Mimosoideae subfamily of Leguminosae is a widespread species with considerable variation in phenotypes even among individual plants in the same area. This species has also generated varied interpretations as to its nomeclature. Catclaw mimosa sometimes becomes a brush species (Scifres, 197, p. ) on overgrazed and/or underburned ranges Readers were referred to the description and line drawing in Vines (1960, p. 508) and the description/discussion in Powell (1988, ps. 193-194). The latter author remarked that although catclaw mimosa provides browse for wildlife and livestock and is a locally important bee plant, it is also a major invader of semidesert grassland in the Trans Pecos Region. Scifres (1980, ps. 52-53) quoted work indicting that catclaw mimosa propagates sexually as well as asexually via rootcrown sprouting. Plants presented in these two photographs were growing on the Excellent condition class hillslope range shown and described above. Val Verde County, Texas. October, plants were in a nonsexual stage of phenology.

Organizational Note: Other examples of catclaw mimosa (in full-bloom) growing on desert foothill range in the general Sonoran Desert Region were presented below in the Stockton Plateau portion of this chapter. Incidentally, this organization and examples presented provided some indication as to distribution (geographic range) of catclaw mimosa.

74. Bluntleaf or anwless spike moss (Selaginella mutica)- This vascular cryptogam constituted the lowest (ground cover layer) herbaceous layer on the Excellent condition class range of semiarid mixed prairie-shrub savanna shown above (range site: Low Stony Hills, West). This spikemoss species grew on spaces of shallow soil situated between outcroppings of limestone that were largely devoid of other plants. Bluntleaf spikemoss grew in closer proximity to cespitose grasses like sideoats grama, green sprangletop, and slim tridens than shrubs like Texas kidneywood and catclaw mimosa. Presence of spikemoss on this range and representing an important rangeland cover type and range site was an example of the fact that range plants include an extremely diverse spectrum just among vascular plants (without even considering fungi, algae,and microorganisms). This demonstrated to beginning students in Range Management that a practical understanding of our native grazing grounds requires a practical, working knowledge of many different species of organisms traditionally regarded as plants. Rangemen must understand the fact that there is more to the range plant community than grass and brush. Spikemoss populations on this range that was in a very high state of succession (not far below climax) also furnished evidence of the diversity and breadth of forb category or group of range plants even in absence of meaningful disturbance. Forbs "ain't" just "damned weeds" or, for that matter, "purty little wild flowers". (This did not imply that spikemoss is never a weed because it sometimes is a noxious plant. Nor did this mean that this native species cannot be enjoyed simply for its beauty because it was by this author/photographer.) Val Verde County, Texas. October: following a long period of abundant rains.

75. Dense colony of Texas wintergrass or, sometimes, Texas needlegrass (Stipa leucotricha)- A local single-species stand of Texas wintergrass was presented as an illustration of several important lessons to beginning rangemen. First is the refesher that Stipa species are dominants of several range types within the mixed and true prairies and associate species in others of these as well as on some tallgrass prairie cover types. Stipa species were clearly the dominants of the pre-Columbian Pacific bunchgrass prairie of California. Various ecologists have offered varying interpretations of associations and dominant species of North American grasslands. Some authors such as Dodd (in Gould, 1968, ps. 326-332) placed Stipa species as the dominants of more grassland associations than any other genus. This included the Gulf Coastal Prairie for which Stipa leucotricha was listed as first dominant. Other authors did not follow the view of Dodd who was probably the most extreme in according Stipa dominant status. At least Dodd was consistent in seeing Stipa species as in the role of dominants in North American grasslands, but the precise role, ecological status, relative composition, etc. of many species, including Stipa, has remained uncertain and contradictory for many range types and sites. A second lesson that this Texas wintergrass illustrated was that of secondary plant succession. Throughout much of the geographic range of S. leucotricha former grasslands and savannas were so disturbed by plowing, overgrazing, alternate overburning and underburning, introduction of alien species, gas and oil exploration and development, etc. that most climax range vegetation was (and remains in) some state-- often severe-- of retrogression (ie. range deterioration). For example, this wintergrass stand was on an old road cut. It illustrated the result of natural revegetation, an example of what rangemen call "haired over". A more widespread case is that of "go-back farmland". Much of the land in the Cross Timbers and Prairies vegetational area in northcentral Texas was in row crop production, especially cotton. Cotton production gradually moved west and finally completely away from this area. Former cotton fields were abandoned, often with no other crop to replace them and nothing done to ameliorate the impact of farming. The old-fields (abandoned farmland) were left to "go-back" on their own, and over time, perhaps to the pre-farming climax (if there was enough of a mature soil to support the former potential natural vegetation). This view of secondary succession, like which species were dominant, was not consistent and universally accepted, but the basic Clementsian model (with continual refinement) seemed to explain many of the changes in old-field plant communities over time. Currently much of the go-back ground in this area as well as some of the Edwards Plateau range that is recovering from decades of overgrazing, drought, and so on has Texas wintergrass as a major-- often the major-- species, at least major cool-season species. One of the most common range plant communities in central Texas is a honey mesquite shrub-Texas wintergrass savanna or even a honey mesquite-Texas wintergrass woodland. Whether this is an advanced seral stage on the way back to climax tallgrass prairie or a disturbance climax of indefinite duration is unknown. The current author shares the traditional view that a grassland community of higher successional status can be achieved by grassland restoration practices involving combinations of brush (and, perhaps, weed) control and range reseeding followed by proper grazing management to maintain the restored state of vegetation. Even when this is biologically possible, however, it may not be economically feasible without cooperation from society at large. Historically this was through private landowners working cooperatively with government agencies to provide technical advice and cost-sharing. Without this joint action stable range plant communities like mesquite-Texas wintergrass range can still be managed to conserve basic natural resources and produce commodities (and consumer goods) such as cattle and calves (and beef). In fact some compromise or middle-ground (ie. "half-assed") approachs are possible. For example, mesquite can be reduced to some proportion as measured by cover, density, biomass, etc. (ie. some degree or level of control) leaving the dominant Texas wintergrass and other grasses, forbs, browse and/or brush species. First-hand observations indicated that Texas wintergrass produces such plentiful seed crops so frequently that seed accumulations resulted in high quantities of soil seedbanks. Frequently when mesquite-wintergrass ranges are root plowed Texas wintergrass either remains dominant or regains dominance following one to three years in a pioner stage of annual grasses and forbs. Root plowing undoubtedly severs Texas wintergrass root systems. Some wintergrass plants recover, but clearly there is enough seed to produce new wintergrass seedlings. This bunchgrass species reproduces asexually only by tillering in contrast to the sod-forming and rapid ground-covering characteristics of stoloniferous species like buffalograss and vine mesquite and rhizomatious species like Indiangrass and switchgrass, but S. leucotricha can compete and self-perpetuate through heavy sexual reproduction. The concept of seedbank was a third lesson from this stand of Texas wintergrass. A fourth lesson was that of one of the Four Cardinal Principles of Range Management: Proper Season of Use. Texas wintergrass is a cool-season species and generally goes dormant or semi-dormant by early to mid-summer depending on weather conditions. Forage value is lower in dead herbage such that provision of higher quality feed can be achieved most readily by grazing live herbage. So animals are best moved off of dormant Texas wintergrass ranges onto ranges of warm-season species, especially the climax little bluestem-Indiangrass prairies, or agronomic pastures like bermudagrass, kleingrass, Johnsongrass, Old World bluestems, or sudangrass. The lesson on Proper Season of Use was continued below from another aspect. Stay tuned. Erath County, Texas. April.

76. Examples of Texas wintergrass plants- These plants are in full anthesis. Erath County, Texas. April.

77. Inflorescence of Texas wintergrass in anthesis- Spikelets of S. leucotricha were photographed at flowering with anthers exerted. These and one stigma were clearly visible before this sexy scene suffered the injury and indignity of a J-peg scanning. Erath County, Texas. April.

78. Mature caryopses of Texas wintergrass- The caryopses of Texas needlegrass are covered grains (ie. the hulls or husks, which are the lemma and palea, remain attached to the caryopsis). The retained lemma has a pronounced hardened callus (ie. the tip where the floret was attached in the spikelet) which is sharp and quite capable of penetrating clothing and pucturing the skin or cornea of eyes. It is because of this phenomenon that youth and laymen often know S. leucotricha as "speargrass". The sharp, indurate callus of the lemma is also typical of Aristida species, but Stipa is in a league all its own. Before eradication of the primary screw-worm fly (Cochliomyia hominivorax) puncture wounds caused by penetrating calluses of Texas wintergrass--not wounds from marking lambs or shearing cuts-- were credited as the number one cause of fly stike in Texas sheep and goats. A veterinarian once related to the author a case of a small, long-haired "lap dog" (Canis familaris) brought in with pus and serous liquid oozing out from all under its skin. In spite of treatment the dog died from trama. Upon post-mortem examination the veterinarian, who had grown up on a sheep and goat ranch in the Edwards Plateau, discovered that hundreds of immediately identifiable Texas wintergrass grains had penetrated through the skin and fascia and into the muscle of the ill-fated canine. (One view could be that Texas wintergrass had protected flocks from potential predators.) Puncture wounds inflicted by plant parts are labeled mechanical injury. Range and pasture plants capable of inducing such physical injury are categorized as mechanically injurious plants and are usually included with chemically injurious species to be regrded generically as toxic or poisonous plants. As a consequence of the mechanically injurious feature of Texas wintergrass at the seed ripe stage some people dislike or detest this valuable range grass. The author has even been asked how to kill "that weed, speargrass". Such ignoragnce provides an opportunity for a valuable lesson in fundamental science and art of Range Management. THE FOUR CARDINAL PRINCIPLES OF RANGE MANAGEMENT: Proper Degree of Use Proper Distribution of Use Proper Season of Use Proper Kind and Class of Range Animal. In this case the professor, whose duty it is to "stomp out ignorance", uplifts the third and, perhaps, the fourth of these fundamentals. Simply put: keep livetock off of or get the stock off of wintergrass range once the grains start to form calluses, usually at the soft dough stage. In this case Proper Season of Use is determined by considerations of the range animal based on plant phenological stage. Move animals from ranges having high populations of Texas wintergrass to those having less (eg. browse ranges or those ranges with predominately warm-season species like bluestem, grama grasses, or curly mesquite or pastures of introduced species like kleingrass). The common name answers it. Texas wintergrass is winter range. Grazing systems such as deferred-rotation grazing can be used to help prevent mechanical injury by needlegrass. The Fourth Cardinal Principle may also offer at least a partial solution. Stock those species of animals that are less apt to be injured by the sharp calluses. At the critical seed ripe stage thicker-hided species like beef cattle would likely be less affected than thin-skinned sheep. Reserving range densely populated with Texas wintergrass for the wildlife enterprise is another possibility (ie. deer or quail leases instead of lambs and wool). The other end of the Stipa lemma, which is typically strongly twisted, terminates in a long, prominent, and twisted awn. The awn and callus together make a propagule ideally suited for epizoochory (disseminule dispersal on the outside of animals). In general, awns function to facilitate burial of seed for improved germination. Some awned fruits like the corkscrew-awned Erodium species, whose awns contract and expand with alternate wetting and drying, have been shown by time-lapse photography to bury themselves very effectively. The morphological structures of range plants, especially the Gramineae, are some of the most interesting from the standpoint of adaptation and survival through natural selection.

79. Merrill bluestem (Andropogon edwardsiana= Bothriochloa edwardsiana)- This delicate bluestem is an endemic species identified only in three counties in the Texas Edwards Plateau. It is locally abundant under proper management, but it is a decreaser and hence readily grazed out under imporper, abusive management such as overstocking. A pretty grass as well as a valuable species. Texas Parks and Wildlife Kerr Wildlife Management Area, Kerr County, Texas. October. Seed-shatter phenological stage.

80. Sexually reproductive shoots of Merril bluestem- Texas Parks and Wildlife Kerr Wildlife Management Area, Kerr County, Texas. October. Seed-shatter phenological stage.

81. Eastern redbud (Cercis canadensis)- This native shrub or small tree of the Caespalpinioideae subfamily of the Leguminosae has a geographic range from Ontario to the mountain ranges of the general Chihuhuan Desert region. Redbud is often an associate of flowering dogwood in the eastern decuiduous forest where the two dominate the second woody (= under shrub) layer. Farther west eastern redbud occurs without flowering dogwood either as a more or less solitary shrub on grasslands or, more commonly, associated with the dominant shrubs of those locales. The deer-browsed individual seen here was growing on the Texas Edwards Plateau where it is a very valuable browse species associated with numerous shrubs like true mountain mahogany, Texas buckeye (Aesculus glabra), Texas persimmon (Diospyros texana), agarito (Berberis trifoliolata), live oak, whitebrush (Aloysia lycioides), and other legumes like honey mesquite (of course) and Texas mountain laurel (Sophora secundiflora). That's just for starters! Kerr Wildlife Management Area, Kerr County, Texas. June.

82. The red "buds" of redbud- The namesake "bud" of this brightly colored native legume is actually the open floral bud with its fully developed inflorescence. Branches of this shrub are to a great degree covered by multitudes of this bright pink or light red flowers which senese before any of the baby cordate leaves appear. The woods from the eastern deciduous forest through to the parts of the Great Plains such as the Edwards Plateau are ablaze in early spring with flowers of redbud, often accompanied by other spring-blooming shrubs such as flowering dogwood (Cornus florida). The example presented here was in the Western Cross Timbers of northcentral Texas (Erath County). March.

83. Bounteous beauty of spring up close- Close-up views of the inflorescence (and individual flowers thereof) of eastern redbud at full bloom. From other than very close examination the flowers of redbud appear to be papilionaceous. They are not in spite of an "almost papioionaceous corolla" (Smith 1977, p. 153). Instead redbud has the flower of the Caesalpinoideae and not the Papilionoideae subfamily of Leguminosae. Erath County, Texas. March.

84. Dull-colored fruit of redbud- It is the fruit type, legume, and not the flower type or structure that distinguishes and designates members of the Leguminosae. These fully ripe and starting-to-dehisce (split open) legumes were on a redbud growing on a clcareous outcropping in the Grand Prairie of northcentral Texas. Tarleton StateUniversity Hunewell Ranch, Erath County, Texas. October; fruit-ripe phenological stage.

85. Texas mountain laurel or mescalbean (Sophora secundiflora)- Leaves and inflorescence of a papilionaceous legume shrub regarded by many Texas native plant enthusiasts as one of the most beautiful plant species in the Edwards Plateau (the famed Texas "hill country"). It is often a very palatable shrub, but it can be highly toxic to all species of ruminant livestock and stockmen must be vigilant. Mountain laurel has high ornamental value for landscaping with native plants. Note on ethics of transplanting native plants: In most cases propagation of native plants should be from fruits or seed and NOT by digging live plants and hoping (often in vain) that transplants will somehow miraculousy survive the trama. Root grubbers are a scurge on the land. Obviously grubbing-- and almost all other means of killing-- brush and weed species (including situations where mescalbean can poison livestock) is an exception. This author holds it to be a self-evident inalienable right and patriotic duty to kill such noxious species as mesquite, huisache, prickly pear, junipers, whitebrush, greenbriar, etc. Valuable species being used for native landscaping (eg. mountain laurel) are not noxious species in that context and they should be propagated from seed (or cuttings). Kimble County, Texas. March.

86. Legumes and leaves of Texas mountain laurel- When fruits of mountain laurel mature they can be gathered, kept in storage, and planted at the appropriate time. This and not the sacrilegious digging of plants from the shallow soil of the Edwards Plateau (or any other land) is the proper way to propagate valuable plants. The beans of mountain laurel are toxic to livestock if chewed and crushed so as to be absorbed, but apparently most seeds pass harmlessly through the gastro-intestinal tract intact though scarified (which may enhance germination). It is the leaves that are the major poisonous part of mescalbean. Kimble County, Texas. May.

87. Mexican buckeye (Ungnadia speciosa)- Here is another shrub or small tree that is poisonous. This monotypic genus of the soap-berry family extends into Mexico ranging up into the Trans Pecos region of New Mexico and Texas north-and eastward into the Edwarads Plateau, Cross Timbers and Prairies, Blackland Prairie, and into the Coastal Prairies and Marshes. Kimble County, Texas. April. Flowering shoot of Mexican buckeye showing new leaves, inflorescences, and last year's fruit. Detail of flower. Kimble County, Texas. April.

88. Fruit-bearing leaders of Mexican buckeye- Details of leaves, immature fruit, and mature bark on shoots of Mexican buckeye. Kimble County, Texas. May.

89. Agarito, algarito, or hollygrape (Mahonia trifoliolata= Berberis trifoliolata)- Algarito is one of many shrub and small tree species common in the Edwards Plateau and Rio Grande Plains of Texas. In fact, agarito grows in eight of the ten Texas vegetational areas. The fruit is valuable for wildlife, but excessive cover of red hollygrape is a brush problem. Lampasas County, Texas. April.

90. Texas or black persimmon or chapote (Diospyros texana)- This is another widely distributed shrub (or small tree) in Texas. It grows in seven of Texas' land resource areas ranging from the Coastal Prairies and Marshes vegetational area to the Cross Timbers and westward across the Rio Grande Plains to the Edwards Plateau and Trans Pecos Basin and Range area. Fruit of Texas persimmon is valuable for wildlife from birds to ruminants and it provides shade and general cover, but it is often a major woody invader requiring brush control practices. Black persimmon has definitely increased in cover with European influence like historic fire exclusion and overgrazing especially in the frontier heyday beginning with the introduction of ranching by the Roman Catholic Church. Welder Wildlife Refuge, Aransas County, Texas. May.

91. Texas persimmon- The showy, smooth, grey bark-- often on intricately twisted trunks-- of this species is a foolproof feature for identification. Llano County, Texas. October.

92. Smooth or sugar hackberry, sugarberry, or palo blanco (Celtis laevigata)- This is a widely distributed species (Virginia to Florida westward to New Mexico and northward to Illinois) with many recognized varieties and much ecotypic variation across it's geographic range. It grows on fertile bottomlands, where it frequently reaches large dimensions, and on infertile, generally harsh habitats such as shallow rock outcrops where the species survives at dimutive sizes. There has been considerable author-to-author variation in treatment of taxa below species level. Sugar hackberry is a common component of various range types and sites. In Texas for example it is frequently a dominant woody plant in various range communities in both the Edwards Plateau and the Rio Grande Plains and it occurs singly and in small thickets through parts of adjoining vegetational areas like that of the Coastal Prairies and Marshes. Celtis species provide fruits that are of value to species of smaller wildlife like birds and rodents. Their twigs, buds, and leaves are taken less frequently by browsing animals. Sugarberry and netleaf hackberry (C. reticulata= C. laevigata var. reticulata) are usually more important as brush species (noxious woody plants) whose cover and density increased under disturbances that induced range deterioration such as overgrazing, underburning, oil and gas development, and abandonment of farm land. In other words hackberry, like most of the other shrubs in this section, are invaders rather than climax species or potential natural dominants of range communities in higher seral states. They are typically indicator plants: indicative of range retrogression. Mills County, Texas. October.

93. From last year and for this year- Two leaders of sugarberry, smooth hackberry, or palo blanco (Celtis laevigata var. laevigata) with last year's fruit and current year's pistillate and staminate flowers. New leaves are about three/fourths growth. Details of unisexual flowers were shown in the next two sets of photographs. West Cross Timbers, Erath County, Texas. April.

94. Spring time for sugarberry- Two views of the pistillate and staminate flowers of smooth hackberry, sugar hackberry, or sugarberry. The first slide gave a general view of the inflorescences (along with new spring leaves) of Celtis laevigata var. laevigata. The second slide showed details of the flowers of this monoecious species (all Celtis species are monecious) with pistillate (female) flowers at left and staminate (male) flowers to the right along on portion of a leader. West Cross Timbers, Erath County, Texas. April.

95. "...male and female created them" (Genesis 1: 27 KJV)- Two slides of sexual reproduction in sugarberry, smooth hackberry, or southern hackberry. In both photographs female (pistillate) flowers at left and male (staminate) flowers at right on leader. A corolla is lacking in pistillate flowers though there is a calyx of five or six sepals. Gynoecium (generic term for female part orf flower; carpels collectively) is unicarpellate (each ovary has one suspended ovule) with two stigmas. The androecium (general term for male part of flower; more specifically, stamens collectively) consist of five or six stamens. West Cross Timbers, Erath County, Texas. April.

96. Pair of drupes- Two drupes on sugarberry, smooth or southern hackberry (Celtis laevigata var. laevigata). This fruit was on a leader that was bearing just-opened monoecious flowers. Drupes were also in the immediately preceding two photographs where their close proximity to newly opened flowers was shown. Fruit got sole emphasis in this shot. Drupe is a fruit type defined as being fleshy and indehiscent with a single seed inside a stony or boney endocarp, the innermost layer of the fruit wall (Smith, 19789, p. 65, 69). West Cross Timbers, Erath County, Texas. April.

97. Catchy branching pattern in sugarberry- A combination of alternate branches coming off of opposite sides of a leader is a frequent branching arrangement in Celtis species, especially C. laevigata. Perhaps this pattern permits large numbers of leaves with a minimal degree of shading so as to facilitate photosynthesis in forest canopies. Would make a eye-catching pattern for neck ties, particularily for dressed-up foresters. Erath County, Texas. September; fruit-ripe stage.

98. Shiny leaves and sweet fruit (well, sort of)- Leaves and fruit of sugarberry shown in photographs that featured leaf position and density along with a better-than-typical crop of fruit. Fruit type in Celtis species is a drupe. Fernald (1950, p. 553) remarked that these sweet-tasting drupes were basis of the name Celtis as used by Pliny for what he termed lotus. Anyway, wildlife of various species consume this fruit and undoubtedly contribute to dispersal of Celtis species. Erath County, Texas. September; fruit-ripe stage.

Texas oak, Texas red oak, or Spanish oak (Quercus texana= Q. shumardii var. microcarpa in part= Q. shumardii var. texana in part= Q. buckleyi)- This list (and it was probably not complete) showed many of the scientific names used at one time or the other for a small, often nearly shrublike, oak that is widely distributed in Texas. Quercus texana has long been the more widely accepted binomial for this small oak, but periodically valid claims and cases were made for all of those listed here. Currently, Q. buckleyi is in favor and pretty much the accepted scientific designation (Diggs et al., 1999, p. 714). This species has proved to be such a little tree to have caused so much taxonomic battle to paraphrase and apply Abraham Lincoln's assessment of Harriet Beecher Stowe. More importantly from the standpoint of range vegetation is the fact that Texas or Spanish oak is one of the more important Quercus species in the Edwards Plateau. Texas oak is also widespread and extremely important as a range feed plant in the Cross Timbers and Prairies vegetation area (Dillard et al., 2005, p. 47) that borders the Edwards Plateau to the north. Spanish oak is in the red or black oak subgenus (Erythrobalanus) and requires two growing seasons for production of mature acorns, but when individual trees bear fruit it is typically an abundant harvest. In addition to large mast crops Texas oak furnishes abundant browse which, on this small tree, is less apt to grow beyond reach of browsing animals.

99. Catkins of Texas, Texas red, Spanish, or spotted oak- The obviously plentiful load of "blossoms" shown here is a promishing indication of an abundant crop of acorns two autumns from now. Erath County, Texas. August.

100. Inside the crown of Texas oak- General appearance of leaves and acorns on leaders of Texas, Texas red, or Spanish oak. Erath County, Texas. August.

101. More of Texas red oak- Detailed view of leaves and acorns of Texas or Spanish oak. A "sample" of the current ripening mast crop representative of this small but valuable oak. More details of acorns of this species follow. Erath County, Texas. August.

102. Mast of Texas oak- Acorns of Quercus texana ( = Q. buckleyi) laid in various positions to show features of cup and nut. As shown here, there is considerable variation in the extent to which the cup encompasses the nut in Texas oak. Acorns are small with this comparatively small size of acorns corresponding to the small size of adult trees of this species. As explained above, however, the generally biennial nut crop is frequently, even typically, one of high yield. Texas red oak is certainly one of the most important mast producers in both the Edwards Plateau and Cross Timbers and Prairies vegetational areas. Erath County, Texas. August; ripe-fruit stage.

103. Whitebrush, whitebush, beebush, palo amarillo, or jazminillo (Aloysia gratissima= A. lycioides var schulzii= A. ligustrina= several other combinations of these taxa)- This member of the verbena family (Verbenaceae) grows from Nuevo Leon and central Sonora north to Texas and New Mexico (depending on how the various taxonomic levels are treated). It is a species of the Sonoran Desert (more abundant in alluvial soils and desert washes). It is also common, even abundant at local scale, in southern Texas from the Rio Grande Plains through the Edwards Plateau, Trans Pecos Basin and Range, and even as far as the southern edge of the Cross Timbers vegetational areas. Whitebrush is primarily important in Range Management as a brush species. Mismanagement (often over a very long period in human time scale) of myriad forms lead to invasion by whitebrush the same as for noxious native legumes, cactii, and numerous other kinds of plants shown frequently throughout this presentation. Economic and ecological importance of whitebrush as a brush species (noxious woody plant) became increasing important as this species increased tremendously in percentage of total plant cover from that of the virgin vegetation to the present brush (= invader) status with disturbances of all forms by European man. Climate changes may have been a factor in the increase of whitebrush as well as that of associated native woody species. Scifres (1980, p. 116) described whitebrush as "an aggressive invader" that had become a major brush problem in Texas especially in the Edwards Plateau and adjoining parts of the Rio Grande Plains. Whitebrush is one of several acomponent species in the various forms of the "mixed brush type", especially in the Rio Graqnde Plains (Scifres, 1980, p. 30), but it also occurs "pure stands" or thickets. This latter phenomenon exists in particular on moist, fertile bottomland sites such that whitebrush is an indicator plant of rich, potentially arable soils (Scifres, 1980, ps. 32, 116). The common name of beebush correctly described the value of this species as a "bee plant", a nectar-producing species of importance for both the domestic and naturalized honey bee (Apis mellifera). It's major value to wildlife is as cover (both shade and coverts). Whitebrush is sometimes important as a range plant that is poisonous to horses in which it induces a rickets-like disease (Kingsbury, 1964, ps. 294-295; Sperry et al., 1964, p. 8; Burrows and Tyrl, 2001, p. 1169). First and second photographs taken in Llano and Mills Counties, Texas, respectively (both in October).

104. Limb or large branch of whitebrush- The typical branching pattern of whitebrush leaders was shown with the dried fruit-bearing spikes or racemes conspicuous. Mills County, Texas. October.

105. Close-up view of whitebrush fruit and leaves- The dried racemes or spikes with the fruit-bearing bodies of whitebrush were shown along with the narrow- to lanceolate-oblong leaves. Whitebrush fruit is a tiny schizocarp produced inside of the floral bracts that comprise the raceme or spike inflorescence. Mills County, Texas. October.

106. Whitebrush inflorescences on shoot apices- Live shoots with recently opened flowers along with dead and decomposing leaders from former seasons. Mills County, Texas. October.

107. Allthorn, spiny allthorn, crown-of-thorns (Koeberlinia spinosa)- Allthorn is a shrub, often a noxious one, that is a common component of scrub communities, especially in the Rio Grande Plains of Mexico and south Texas westward and northward into the Edwards Plateau, Rolling Red Plains, and Trans Pecos Basin and Range areas. Technical Note: The partially out-dated reference, Brush Management - Principles and Practices for Texas and the Southwest (Scifres, 1980), is still the definitive bound source for descriptions, ecology, and key biological aspects of the major brush species in Texas and adjoining parts of neighboring states. Many of the specific brush control practices given by Scifres (1980) are obsolete (eg. 2,4,5-T, arguably the most economically effective broad-spectrum herbicide ever, has been off the market for nearly two decdes). For the current best brush control practices one should consult the various Cooperative Agricultural Extension Services, Natural Resources (= previously, Soil) Conservation Service, and/or field representatives of the various companies offering products and services for brush and weed control.

108. Landscape-scale view of Texas Edwards Plateau- It was briefly discussed earlier that the pre-white man vegetation of the Edwards Plateau could not be determined accurately even though several learned travelers left written observations of Plateau plant communities. There is one point upon which there is consensus: woody vegetation,  especially of Juniperus species, has increased tremendously in the last century. This is a severe state of range deterioration; of ecological retrogression due to many factors, including overgrazing, but mainly cessation of natural fire regimes. Simply stated, the climax Texas Edwards Plateau mixed prairie-savanna cannot be maintained  without the use of prescribed fire. The most recent research and professional experience indicated that prescribed fires must be hot fires set in summer and not cool spring burns.    Much of the Edwards Plateau like the Fort Worth, Grand, and North-Central Prairies is being invaded at an alarming rate by two species of cedar of juniper: red-berry juniper (Juniperus pinchotii) and Ashe or blue-berry juniper (Juniperus ashei). Red-berry cedar is one of the few conifers that resprouts; blue-berry juniper does not resprout. Both are native species, but in virgin conditions were largely confined to rocky, hilltop habitats or those along streams, both of which were largely protected from fire. Both the Indians and early European frontiersmen fired the woods and ranges of Texas routinely. While this practice continued through most of the 1950s and even early 1960s in the Texas Pineywoods it largely ceased in other parts of Texas with the advent of barbed wire fencing in the 1880s. The Texas legislature even outlawed the setting of range fires as the open range passed into the “big pasture” and, later, homestead eras. As such, and combined with overgrazing (which reduced the herbage necessary to fuel grassland and savanna fires), oil and gas development, farming and abandonment of farms, etc. the Texas range country eventually became a brush patch.  Much of the Edwards Plateau has become one massive cedarbrake made up of both red-berry and blue-berry juniper that continues to grow like a cancer on the land.   This landscape view shows this cedarbrake in the background, but the foreground is an example of excellent management of Edwards Plateau savanna range. Prescribed burning at intervals of roughly three to seven years have maintained the mixed prairie-live oak-sumac savanna. Dominant grasses are vine mesquite, little bluestem, sideoats grama, Texas wintergrass, silver bluestem, buffalograss and curly mesquite. The tall big-leafed forb is the Eurasian weed, flannel mullein (Verbascum thapsus). At this density mullein is not a problem but merely a conspicuous plant. Other forbs vary from  valuable forage species like redstem filaree (Erodium cicutarium) and Texas filaree or stork’s-bill (E. texensis), Engleman daisy (Engelmannia pinnatifica), and the annual Texas bluebonnet (Lupinus texensis) to invader species like Baldwin ironweed (Vernonia baldwinii).  There is such a diverse mixture of grasses, forbs, and shrubs and of cool- and warm-season species that, given adequate rains, there are usually some green species on Edwards Plateau ranges yearlong. The scene here is a textbook example of proper use of prescribed burning and outstanding grazing management. This pasture is part of a High Intensity Low Frequency System with seven pastures and one herd with a 35 day graze and a 150 day rest. Average stocking rate is 20 acres per Animal Unit Year. Range animals are white-tail deer and cattle (no sheep or goats) with cattle used to improve the range for deer. The secret to any successful brush reduction (= control) program is follow-up sound grazing management.  Any investment made in brush control (or any range improvement and development practice) will be a waste of money, labor, hopes, etc. without sound grazing management, the key ingredient to range and pasture management.

Texas Parks and Wildlife Department Kerr Wildlife Management Area, Kerr County, Texas. Vernal aspect, June. FRES No. 32 (Texas Savanna Ecosystem), K-77 (Juniper-Oak Savanna), SRM 734 (Mesquite-Oak), Redlands range site. Improper designation by Kuchler of Juniper as a dominant species of the vegetation type was addressed under the next photograph. Edwards Plateu Woodalnd Ecoregion, 30a (Griffith et al., 2004).

109. Edwards Plateau Live (= Plateau) Oak-Post Oak-Mesquite- Mixed Prairie Savanna- This a detail interior shot of the cattle and deer range seen in the preceding slide.  This range was burnt three months prior to the time of the photograph. The beautiful (ie. dead) cedars are the non-sprouting blue-berry juniper. They have been killed while the post and live oaks were unharmed by the spring prescribed fire. Even the biennial flannel mullein which overwinters as a large rosette was unharmed by the prescribed burn. Dominant plants in this view are vine mesquite, sideoats grama, little bluestem, hairy grama and infrequent threeawn species. Cool-season annual forbs like filaree have completed their annual cycle and died. This pasture was last burned prior to this spring’s burn five years previously. A five-year fire frequency is recommended for maintenace of this climax vegetation. Texas Parks and Wildlife Department Kerr Wildlife Management Area, Kerr County, Texas. Vernal aspect, June. FRES No. 32 (Texas Savanna Ecosystem), K-77 (Juniper-Oak Savanna), SRM 734 (Mesquite-Oak), Redlands range site. The Kuchler designation of Juniper is technically incorrect because, as can be best determined, this part of the Edwards Plateau was grassland and not woodland or forest (see Amos and Gehlbach, 1988 as well as standard generic descriptions like Correll and Johnston, 1979). Edwards Plateau Woodla;nd Ecoregion, 30a (Griffith et al., 2004).

110. The goal of a prescribed burn on Edwards Plateau mixed prairie-oak savanna range- A dead blue-berry cedar and robust vine mesquite and Texas wintergrass. Vine mesquite was released from cedar competition and the wintergrass, though nearing completion of its annual growth cycle at time of burn, was not harmed by the prescribed fire. Same range as seen in the preceding two slides.

111. Edge of Edwards Plateau mixed prairie-oak savanna and a cedarbrake of Ashe juniper- Dominant grass of the mixed prairie grassland was silver bluestem. Little bluestem was associate species. Some perennial three awns, sideoats grama, hairy grama, and dropseed (Sporobolus) species. Forbs were locally absent. Texas parks and Wildlife Kerr Wildlife Management Area, Kerr County, Texas. October. Autumnal aspect. FRES No.32 (Texas Savanna Ecosystem), K-77 (Juniper-Oak Savanna). SRM 734 (Mesquite-Oak). Cedarbrake: SAF 66 (Ashe Juniper-Redberry [Pnchot] Juniper). Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

.

112. Cedarbrake of blue-berry or Ashe juniper and red-berry juniper- A beginning historical note on syntax: the correct spelling is “brake” which according to Merriam-Webster (1995) is a term tracing back to 1563 used in reference to “rough or marshy land overgrown usually with one kind of plant”. The single- or two-cedar species stands or rough, rocky land and the single-species stands of dense bamboo or “cane” fit this description, hence cedarbrake and canebrake, respectively. “Cedar break” is a correcty spelling only in the context of junipers on rough land that is designated as “breaks” as in a Breaks range site.  Ecological analyses, including personal written accounts of observant  frontiersmen and early settlers, strongly suggests that on the virgin Edwards Plateau range dense stands of cedar like this were restricted to habitats not likely to burn. With the cessation of fire by modern man as a combination of ignorance, arrogance, fear, overgrazing, subdivision of rangeland into ever smaller parcels, risk to property, etc. the cedars “spread like wild fire” (to employ an ironic pun). Brush like this is not only useless for forage and browse production for livestock but it is also worthless for wildlife habitat except for a few “dickey birds”, porcupine (Erethizon dorsatum), and occasional other rodents like wood rats (Neotoma spp.). It is marginal even for the wood rats as they prefer mesquite or cactus thickets (Davis, 1978, ps. 218, 221). Cedarbrakes are not preferred for shade because larger animals, except feral swine, cannot get into them (at least without being driven there by dogs). “Wild” hogs seek protection of the nearly impenetrable cedar thickets that are a safe haven for these highly destructive feral species which are predators of young sheep, goats, and deer. This is a control or check plot of untreated cedarbrakes on the Texas Parks and Wildlife Department Kerr Wildlife Management Area. It is an example of afforestation or a man-made postclimax vegetation but one that is a disturbance climax as an advanced stage of range retrogression. Unlike such disclimaxes as cheatgrass range and the Rio Grande Plains brush country this case of noxious range plants can be “cured” quickly and efficiently.  Some cedarbrakes like this one occurred naturally on certain “fire-resistant” sites (eg. breaks sites) of the pre-European Edwards Plateau vegetation (cedar breaks would be the more precise spelling for natural cedar communities developing on rough, rocky land designated as “breaks”). Such dense stands growing where there was not enough fuel to carry fire are part of the climax or potential natural vegetation, and this slide can be interpreted as an example of climax juniper forest. Natural cedar breaks should be preserved. Dickey birds need homes too. Some lof these are rare or endangered species like the golden-cheeked warbler (Dendroica  chrysoparia). This warbler builds its nest from the stringy, exfoliating bark of mature Ashe or blue-berry juniper and thus requires cedar as part of its habitat. It also requires oak trees and nests on rocky hills such as the Balcones Canyonlands where, again, natural fires were unlikely.  Texas Parks and Wildlife Department Kerr Wildlife Management Area, Kerr County, Texas. June. This can be interpreted as a natural juniper forest phase of FRES No. 32 (Texas Savanna Ecosystem), K-77 (Juniper-Oak Savanna), SRM 734 (Mesquite-Oak) or, alternatively, as the pure juniper phase of the general FRES No. 35 (Pinyon-Juniper Ecosystem), K-21 (Juniper-Pinyon Woodland). SAF 66 (Ashe Juniper- Redberry [Pinchot] Juniper). It was discussed under the Juniper-Pinyon Woodland vegetation that this cover type (in its various forms) frequently exist as “islands” within a larger range vegetation type (eg. isolated J-P Woodland communities within an overall mixed prairire grassland) . It could be argued logically that dense stands of juniper growing on “rock piles” like this one and those naturally occurring on the Balcones Escarpment (= Balcones Canyonlands) are just such “islands” of J-P Woodland.

113. Interior of a cedarbrake- This is the understory (absence thereof) of a more open  cedarbrake. Light is so limited in a dense cedarbrake that it cannot be photographed well using natual light. This sparse understory has roughly the same species composition as the herbaceous vegetation of the Edwards Plateau savannah. The most obvious exception is the near absence of annual forbs like the nutritious filarees under heavy duff of dense juniper stands. Cedar breaks often have small open areas within the stand which can be grazed if animals will move through the dense woody vegetation like that seen here to get to the feed. On range having a mosaic of cedarbrakes and open country the stocking rate is about 80 acres per Animal Unit Year which is ¼  the grazing capacity of the Excellent condition Edwards Plateau savanna range seen previously.

114. Another view of interior of a cedarbrake- In this "open" (by cedarbrake standards) stand of Ashe or blue-berry juniper the typical branching pattern of this Juniperus species was obvious. Note almost total absence of herbaceous species and of any other woody species. One cannot help but have respect for those tough characters known as "cedar-choppers" who cut this brush for fence posts and stays. (Texans are tough and ornery enough as it is, but cedar-choppers are the toughest of the "rough-and-tough", and they would be the first ones to come to the aid of a stranger.) Texas Parks and Wildlife Kerr Wildlife Management Area, Kerr County, Texas. October.

115. The alternative to extensive cedarbrakes in the Edwards Plateau- This was a former dense stand of red-berry and Ashe juniper (like that of the preceding slide) that increased to the ecological status of a woody invasion thereby displacing the natural vegetation of mixed prairie-oak-sumac-juniper savanna. The cedarbrake was bulldozed 23 years prior to date of this photograph. Prescribed burning was applied seven years and again one year prior to the current vegetation. Grasses include little bulestem, Indiangrass, silver bluestem, sideoats grama, hairy grama, Texas wintergrass, perennial dropseeds (Sporobolus spp.), and threeawn species. Live or plateau oak and post oak as well as junipers are the dominant trees. Immature individuals of these species exist as shrubs. The dominant shrubs are flameleaf sumac (Rhus copallina), seen at the extreme left, and skunkbush sumac (R. aromatica= R. trilobata). Rhus species increase with fires more than most woody species. This is particularly the case for the rhizomatous species like flame-leaf sumac. Skunkbush is the better browse plant, but deer and goats readily browse flame-leaf especially after they become accustomed to it.   Texas Parks and Wildlife Department Kerr Wildlife Management Area, Kerr County, Texas. Vernal aspect, June. FRES No. 32 (Texas Savanna Ecosystem), K-77 (Juniper Oak Savanna), with the designation of dominance to Juniperus species in error. SRM 734 (Mesquite-Oak), Low Stony Hills range site. Edwards Plateau Woodland Ecoregion, 30a (Griffith et al., 2004).

116. Fleshy seeds and needles of Juniperus ashei- This species is commonly known variously as Ashe, post, blue-berry (or, blueberry), rock, or white juniper or cedar (cedar is the more widespread common generic name for Juniperus among rural people). As with eastern red cedar blue-berry cedar does not resprout following top removal by burning, cutting, breaking, etc. It is more palatable (or less unpalatable) to Spanish goats and deer than the red-berry (= Pinchot’s) cedar or eastern red cedar. Is it any wonder that in absence of something like fire to control the natural rate of increase this— and numerous other —Juniperus species have taken over such immense areas of former grassland and savanna range? Arbuckle Mountains, Murray County, Oklahoma. July.

117. Leader of redberry (or, red-berry) juniper, Pinchot's juniper, or redberry cedar (Juniperus pinchotii)- Needles and immature fleshy seeds of the redberry juniper. Typically the branches of this Juniperus species are more "scraggly" or have a "skiner" appearance (ie. appear less "filled out") than Ashe or blue-berry juniper. The outstanding (outstandlingly bad) feature of Pinchot's juniper from a range management standpoint is that it is one of the few sprouting Juniperus (for that matter, coniderous) species. Natural and prescribed fire keep individuals of this species low and from reaching adult size, but generally (and most unfortunately) do not kill this insidious conifer. Tarleton State University Hunewell Ranch, Erath County, Texas. September.

118. Needles and mature fleshy seeds of redberry or Pinchot's juniper- The flsehy seeds of red-berry cedar take on a rust or burnt brown color at maturity. These mature "berries" (of course not a berry; not even a fruit) are the source of the more comonly used common name. It should be noted that from this and the preceding slide that redberry juniper has been observed to produce fewer seeds than most other "cedars" or junipers that are found on range such as blueberry, eastern red cedar (Juniperus virginiana), and western juniper (J. occidentalis). Logically, this reflects the phenomenon of resprouting (asexual reproduction) of redberry juniper. Tarleton State University Hunewell Ranch. September.

119. Field identification feature of redberry or Pinchot's juniper- In spite of common name designations of blueberry vs. redberry juniper mature fleshy seeds of both of these range-infesting, weedy Juniperus species have brown or dull red coloration. Seed color is meaningless in distinguishing between the sprouting redberry and the nonsprouting blueberry or Ashe juniper. Instead the foolproof feature that can be used to distinguish between species of these brush species is prsence of a flaky white exudate (apparently a form of rosin) on twig stems (typically the more terminal portions of branches) and needles of the sprouting redberry juniper. Examples of such rosin patches or rosin flakes were visible in these two branches. Tarleton State University Hunewell Ranch. September.

120. The coniferous curse invades Hereford Heaven- The natural bluestem and Indiangrass pastures of the ancient Arbuckle Mountains were the heart of a major purebred beef cattle producing area known as Hereford Heaven. In the last third of the Twentieth Century the outstanding mixture of tallgrass prairie and bluestem-grama mixed prairie that served as the basis of this famed cradle of beef seedstock became invaded with Ashe juniper and eastern red cedar along with associated woody species like hackberry and persimmon (Diospyros virginiana). This was often to the point of almost total elimination of the former virgin grassland as seen clearly in this sad scene. Both eastern red and blue-berry cedar have invaded this Edge Rock range site which still has a tallgrass prairie remnant dominated by big bluestem and Indiangrass which are clearly visible. Sideoats grama is the dominant associate. It would take guts to ignite this mess of cedar, but deferment of this range for one grazing season followed by a hot spring prescribed fire would restore this prairie to pristine condition. Recall that both of these junipers are nonsprouting species and that vegetative growth and sexual reproduction in big bluestem is “stimulated” by spring fires. The only other brush species of consequence is persimmon which does sprout, but fire will top-kill it. These are the relevant facts about a properly conducted prescribed burn on this rangeland: 1) it will eliminate most of the cedar, 2) it will encourage the tallgrass species, 3) it will set back however many years of growth there is in the persimmon, and 4) the net result is a restored grassland.    Arbuckle Mountains, Murray County, Oklahoma. Estival aspect, July. FRES No. (Plains Grassland Ecosystem), K-62 (Bluestem-Grama Prairie), SRM 709 (Bluestem-Grama), Edge Rock range site.

Balcones Canyonlands

Land forms influenced by the Balcones Fault and part of the Balcones Escarpment (= Balcones Scarp) dramatically mark the southern and eastern boundary of the Great Plains physiographic province. The Balcones Escarpment has traditionally been included as part of the Edwars Plateau although Feneneman (1931, enclosed map, ps. 50-55) distinguised the Edwards Plateau from the Central Texas Section. Students of vegetation, including range scientists, have historically included both of these physiographic unit tol delineate the Edwards Plateau as a distincetive vegetational area (Correll and Johnston, 1979, map 1, ps. 9-10). The Balcones Escarpment has come to be known as the Balcones Canyonlands when designating vegetational, ecological, or general biological aspects of this landscape or large ecosysstem. It is a very apt description as was shown in the treatment presented below from the canyon of Can Creek in Lost Maples Natural Area, Bandera County, Texas.

121. Physiography of the land and physiogonomy of range vegetation in the Balcones Canyonlands portion of the Edwards Plateau was illustrated by a series of four photographs of the interior of Can Creek Canyon..

A plethora of range plant species in a Balcones canyon-- The canyonlands physiographic features and the biological diversity in Balcones Escarpment plant life was striking in this view of Can Creek Canyon. The most obvious plants are the various species of trees. There were at least nine (9)species of trees in this photograph (though not all can be discerned in it). Generally the most common tree species in this general area are the plateau live oak (Quercus fusiformis= Q. virginiana var. fusiformis) and Ashe juniper that is also known variously as rock edear, post cedar, Mexican juniper (Juniperus ashei). The latter was dominant on the canyon uplands seen here as the top of (or above) the limestone bluff in the background and as young trees that recently had invaded the canyon bottomland (present in center midground of this slide). The most common invading tree species obviously was American or western sycamore (Platanus occidentalis). Trees at base of the bluffs that were a red tinge of autumn coloration were large Texas red oak or Spanish oak (Quercus texana= Q. rubra var. texana= Q. shumardii var. texana). The large tree with the rounded crown with prominent green leaves at base of bluff (along left margin of photograph) was Arizona walnut or nogal silvestre (Juglans major). Also present but not individualy discernible in this photograph were post oak, pecan (Carya illinoinensis), eastern cottonwood (Populus deltoides), and Texas ash (Fraxinus texensis= F. americana var. texensis) There were even more species of grass, a partial list of some of the more common ones of which was: bottomland switchgrass, eastern gamagrass, Lindheimer muhly (Muhlenbergia lindhemeri), little bluestem, silver bluestem, Indiangrass, sideoats grama, hairy grama, common windmillgrass (Chloris verticillata), and the naturalized exotic King Ranch bluestem. There were also sedges (Carex spp) and Jamaca sawgrass (Cladium jamaicense) along Can Creek. The generally most common forb (and certainly the largest) was frostweed or white crown-beard (Verbesina virginica). Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal aspect. FRES No. 32 (Texas Savanna Shrubland Ecosystem). K-77 (Juniper-Oak). Variant of SRM 733 (Juniper-Oak). No appropriate biotic community in Brown et al. (1998). Edwards Plateau- Balcones Canyonlands Ecosystem 30c (Griffith et al., 2004).

In a bottomland range in the Balcones Scarp- Another view of the remarkably species-riange plant community presented in the immediately preceding slide. This closer-in shot featured dense regeneration (=reproduction) of American sycamore. These saplings had been produced from seed on the rock-strewn canyon bottom along the banks of Can Creek. Sycamores are deceiving in this regard. The immense size of mature sycamores suggest that this is a climax, but actually sycamore is often a pioneeer or colonizing species, but one that persist into the climax vegetation. Other tree species that were regenerating on this photo-site were eastern cottonwood, Texas ash, bigtooth maple, Arizona walnut, and, of course, Texas red or Spanish oak, the promintent dominant tree species. Dominant grasses were bottomland switchgrass, eastern gamagrass, King Ranch bluestem, Lindheimer muhly, Indiangrass, and sideoats grama. Various other grasses were also present but only in small to "occasional" proportions (eg. hairy grama, buffaalograss, common windmillgrass and the two naturazlized species Johnsongrass and common bermudagrass). Large, rank-growing frostweed was the dominant forb. Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal aspect. FRES No. 32 (Texas Savanna Shrubland Ecosystem). K-77 (Jiuniper-Oak Savanna). Variant of SRM 733 (Juniper-Oak). No appropraite biotic community in Brown et al. (1998). Edwards Plateau- Balxones Canyonlands Ecosytem 30c (Griffith et al., 2004).

Canyonlands panarama- Along the bend of Can Creek exposed canyon walls (bluffs) were topped by upland range vegetation dominated by Ashe juniper with plateau live oak as the associate species. In the bottomland a glade or grassland opeing was dominated by eastern gamagrass, a bottomland ecotype of switchgrass, and Linheimer muhly and with frostweed or white crown-beard as the main (and a prominent) forb. A woodland community made up of numerous tree species surrounded the glade. The large tree in midground was bigtooth maple (Acer grandidentatum= A. saccharum var. grandidentatum; more recently interpreted as A. grandidentatum var. sinuosum); young tree to front and left of maple was American or western sycamore. Large mature Texas red oaks grew along creek banks. Other tree species in this botanically rich range community included plateau live oak, post oak, Arizona walnut, pecan, Texas ash, and eastern cottonwood. Bigtooth maple is likely a relict species from the standpoint of plant geography (not as a sample of pristine vegetation in the sense of a relict area). Polunin (1960, p. 197) "... in the phytogeographical sense are remmnants of an earlier flora that have been 'left behind' while surounding areas have been vacated". In the Edwards Plateau bigtooth maple is in about the easternmost part of its species range. The identification and taxonomic relations of bigtooth maple seem to remain unresolved. It is a "hard maple" (Acer species whose wood is extremely tough and indurate) and is closely related to, if not a variety of, the eastern sugar maple (A. saccharum). It is frequently known by the common name, sugar maple. Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal aspect.FRES No. 32 (Texas SavannaShrubland Ecosystem). K-77 (Juniper-Oak Savanna). Variant of SRM 733 (Juniper-Oak). No appropriate biotic community in Brown et al. (1998). Edwards Plateau- Balcones Canyonlands Ecoregion 30c (Griffith et al., 2004).

Varied vegetation- Interior of the bottomland range vegetation introduced in the preceding photograph. The largest tree is the bigtooth or sugar maple specimen presented in that photograph. On either side of this maple were saplings, mostly of sycamore with some eastern caottonwood. A large individual of Lindheimer muhly (with conspicuous panicle inforesecences) was directly in front of the trunk of the bigtooth maple. Other common grsss species included bottomland switchgrass, eastern gamagrass, little bluestem, and King Ranch bluestem. Note that the King Ranch bluestem was the only non-climax species among dominants. There were scattered specimens of sideoats grama and miscellaneous species that were best interpreted as invaders on this range site, including Texas grama, common windmillgrass, and naturalized common bermudagrass. These were on recently disturbed areas. Frostweed was common.and it's association with climax tallgrass species suggested that frostweed was a member of the climax range plant community. Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal sspect.FRES No. 32 (Texas Savanna Shrubland Ecosystem). K-77 (Juniper-Oak Savanna). Variant of SRM 733 (Juniper-Oak). No appropriate biotic community in Brown et al. (1998). Edwards Plateau- Balcones Canyonlands Ecoregion 30c (Griffith et al., 2004).

122. Banks of a canyonlands stream- Mesic range vegetation had developed on a high bank overlooking Can Creek Canyon.The dominant herbaceous species was Jamaca sawgrass. Eastern gamagrass and a bottomland ecotype os switchgrass were associate species of the herbaceous layer of this diverse range plant community. There were far fewer grass species than in the bottomland habitat and vegetation shown in the preceding of the four immediately preceding photographs Trees of the overstorey included western sycamore (foremost white-bark trunk), post oak and plateau live oak (in midground), and Texas ash, Arizona walnut, eastern cottonwood, and Ashe juniper (in background). Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal aspect. FRES No. 32 (Texas Savanna Shrubland Ecosystem). Variant form of K-77 (Juniper-Oak Savanna). Variant of SRM 733 (Juniper-Oak). Edwards Plateau- Balcones Canyonlands Ecoregion 30c (Griffith et al., 2004).

123. Tallgrass in the canyon (or a bit of Kansas in Texas)- A glade in bottom of Can Creek Canyon had developed into an "island" of tallgrass prairie dominated by a bottomland ecotype of switchgrass with eastern gamagrass as the associate. This is the same basic grass species composition of mesic bottomland sites in the Flint Hills-Osage Questas-Cherokee Lowlands Region in Kansas and Okahoma. Other common species were Lindheimer muhly, Indiangrass, little bluestem, and (no surprise) King Ranch bluestem. Frostweed or white crown-beard was also present (as it was in all microsites that supported tallgrass species in this canyon). A sycamore invasion was underway as saplings of this species known for large trees along watercourses was encroaching on the tallgrass turf. "Trouble in paradise". What was (is) role of fire in this range vegetation? Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal aspect. In context of Landscape Ecology this was a patch of tallgrass prairie in the matrix of K-77 (Juniper-Oak Savanna) and variant of SRM 377 (Juniper-Oak).

124. Mesic slope in Balcones Canyonlands- This bench of land below the canyon of Can Creek supported range vegetation that was much more mesic than that of the larger surrounding Balcones Escarpment environment. In Clementsian Ecology this vegetation was postclimax. The postclimax concept was defined by Allaby (1998): "In the monoclimax model of climax vegetation development, communities differing from the climatic climax, owing to cooller and/or moister conditions than are characteristic of the regional climate". Mature tree on far left was bigtooth maple. Dead snag was of eastern cottonwood. Young saplings on far right were western sycamore. A pecan was in the background. Tallest clumps of grass in right-hand corner were switchgrass. Other prominent grass species were Indiangrass, eastern gamagrass, Canada wildrye, Lindheimer muhly, and little bluestem. Frostweed or white crown-beard was the very noticable forb. This was a tallgrass-sugar maple savanna or perhaps all dominant bottomland hardwoods should be included to identify or label this as a tallgrass-mixed hardwood savanna. The relict bigtooth or sugar maple was, howevr, the characteristic indicator species. Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal aspect. Part of greater FRES No. 32 (Texas Savanna Shrubland Ecosystem), but was not described by the published --the general-- units of vegetation by Kuchler (1964, in Garrison et al., 1977), Society for Range Management (Shiflet, 1994), or Brown et al., (1998). Edwards Plateau;- Balcones Canyonlands Ecoregion 30c (Griffith et al., 2004).

125. Edwards Plateau tallgrass-maple (or mixed hardwood) savanna- Closer-in view of the grand ole specimen of bigtooth maple and snag of eastern cottonwood with an herbaceous understorey of bottomland ecotype switchgrass, eastern gamagrass, Lindheimer muhly, Indiangrass, little bluestem, Canada wildrye, and sideoats grama. Mature pecan was in background. Frostweed was present and prominent. Postclimax range vegetation. Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal aspect. FRES No. 32 (Texas Shrub Shrubland Ecosystem), but no published units for this small spatial-scale postclimax range vegetation.

126. Balcones oaks and ball moss- In the canyonlands of the Balcones Escarpment a large plateau live oak (Quercus fusiformis; synonyms given previously), in foreground, supported a healthy population of ball moss (Tillandsia recurvata) while in the background an even larger Texas red oak (Q. texana= Q. rubra var. texana) spread delightfully sun-lite leaves in an autumn sky. If this ain't Texas Hill Country romance there ain't no such thing. Lost Maples State Natural Area, Bandera County, Texas. October, early autumnal aspect.

127. Ball moss on a limb on the ground- Dead limb of a live oak fell to the ground carrying with it its arboreal hitchhiker, ball moss. Throughout parts of the Balcones Escarpment this commensal epiphyte is a common member of Edwards Plateau range vegetation even though it is often--perhaps, usually--overlooked or ignored. What, if any, contribution this monocot makes to diets of range animals was unknown to this author. The species merited inclusion in any detailed treatment on range plant communities of the southern extremity of the Edwards Plateau-- and, it was emphasized, southeastern terminus of the Great Plains. Kerr County, Texas. October.

128. Out of its nest- Another plant of ball moss that was blown by high winds from its moorings (this one from post oak limb) fell to the leaf-littered ground. While this plant had met its untimely end with dislodgment from its host tree the accident victim was put to the service of educating the next generation of rangemen with inclusion of these and the next two photographs. Bexar County, Texas. February. Post- fruitripe stage and perhaps a stage of semi-dormancy (prior to its recent death).

129.Dried flowers, mature fruit- Closeup views of the inflorescence and mature fruit of the plant of dislodged ball moss introduced immediately above. The fruit of Tillandsia species is a septicidal capsule containing cylinderical or fusiform seeds with an attached plumose appendage. Generally there are only one or two inflorescences per plant.(Correll and Johnston, 1979, ps. 355-356), but this particular specimen had four flowers which undoubtedly maked it as a fecund individual. Bexar County, Texas. February. Post- fruitripe stage.

130. Frostweed or white crownbeard (Verbesina virginica)- This composite of the Heliantheae tribe is a common fall-flowering forb throughout much of the Edwards Plateau. There are numerous species of wingstem (another common name for Verbesina spp.), including some with yellow infloresences, but this is the more prominent and better know one "hereabouts". This forb was associated with climax tallgrass species at every location visited by the author in this canyon. It must be assumed that V. virginica is climax forb. It is a weed in name only. This range forb would seem to have considerable appeal to those who landscape with native plants. Are you looking "native Texans"? Gillespie County, Texas. October.

Stockton Plateau

In introducing the Edwards Plateau it was discussed that the topographic unit or feature designated Stockton Plateau is precisely speaking a part of the Great Plains physiographic province (as is the rest of Edwards Plateau) and not the Basin and Range Province (Fenneman, 1931, p. 50). Students of Texas vegetation, including the definitive authorities Gould (1962) and Correll and Johnston (1979), followed this convention and regarded the Stockton Plateau as part of Edwards Plateau. That precedent was followed below. It was noted emphatically, however, that the traditional Texas interpretation of the western boundary of the Edwards Plateau vegetational or land resource area contrasted drastically with map units of potential natural vegetation (Kuchler, 1964, map in Garrison et al., 1977) and level III Texas ecoregions (Griffith et al., 2004). These conflicting views (if not contradiction at very least lack of complete agreement) among authorities who dealt to large degree with range vegetation was described above in the introduction to Edwards Plateau.

131. Sampler of the semiarid Stockton Plateau- This example of the Stockton Plateau conveyed the harshness and relatively hostile environment of the western Edwards Plateau due to semiaridity, shallow soils, and rapid runoff of scarce precipitation. This was also a fair repesentation of topography characteristic of the general land form of the Stockton Plateau. Range vegetation was extremely diverse. in this classic mixed prairie-shrub savanna. Students should not forget that the Edwards Plateau is the southern extension of the Great plains physiographic province such that this grassland is the "hard-scramble", rock-strewn form or exxpression of the mixed prairie of High Plains and Rolling Red Plains to the north. There was not always a dominant or even set of dominant grasses, but there were many Gramineae species. Some of these in this "photo-plot" included sideoats grama, silver bluestem, little bluestem, fall witchgrass, buffalograss, curly mesquite, plains bristlegrass, Texas cupgrass (Eriochloa serecia), red grama, and blue grama (just for starters). Shrubs were more picturesque, though not dominant (other than aspect dominance) on this high condition class range. Shrubs included Texas sotol (Dasylirion texanun), plateau live oak, catclaw or Roemer acacia (Acacia roemeriana), guajillo (A. berlandieri), catclaw mimosa or wait-a-minute (Mimosa biuncifera), pricklypear (Opuntia spp., with O. englemannii apparently the most common), and littleleaf sumac (Rhus microphylla). Again that was for starters. And of course honey mesquite was preent (it was afterall Texas), but only as an incidental woody species. It is likely that there were several woody and suffrutescent composties like cutleaf bricklebush (Brickelllia laciniata) and broom snakeweed (Gutierrezia sarothrae) but the photographer did not observe these species on this range shown in this photo-plot. Devil River Ranch, Val Verde County, Texas. May, a dry vernal aspect. Edwards Plateau- FRES No. 33 (Southwestern Shrubsteppe Shrubland Ecosystem) Transition between or combination of K-52 (Grama-Tobosa Shrubsteppe) and K-53 (Trans-Pecos Shrub Savanna). Variant of SRM 734 (Mesquite-Oak). Brown et al. (1998) did not provide a biotic community for this range vegetation: would be some Series under Warm Tempearate Scrubland 133. or Warm Temperate Grassland 143. Edwards Plateau- Semiarid Edwards Plateau Ecoregion 30d (Griffith et al., 2004). Rocky Hills range site.

132. Semiarid (western) portion of Edwards Plateau- The Stockton Plateau is technically part of the Edwards Plateau (both geologic units are part of the Great Plains physiographic province). Scene in this photograph captured the essence of both physiography and range vegetation of the driest subunit of the Edwards Plateau. Range plant community was a Great Plains mixed prairie-shrub savanna. Dominant plant growth or life form and taxonomic identity was perennial grasses. Dominance among these grass species was not consistent as with many range types. Instead dominance varied from microsite to microsite. Major grasses included silver bluestem, little bluestem, fall witchgrass, sideoats grama, blue grama, curly mesquite, plains bristlegrass, Texas cupgrass, buffalograss, and red grama. Many of the most important shrubs present were species that are also major woody plant in the Rio Grande Plains and Chihuhuan Desert. Common shrubs included plateau live oak, guajillo, Roemer acacia, sotol, catclaw mimosa or wait-a-minute, littleleaf sumac, and pricklypear species like Englemann pricklypear. Honey mesquite was present as an occasional species and Ashe juniper was even more uncommon in this range vegetation that was in an advanced seral stage and probably approaching climax. Forbs were extremely limited. Devil River Ranch, Val Verde County, Texas. May, a dry vernal aspect. FRES No. 33 (Southwestern Shrubsteppe Shrubland Ecosystem). Transition between or combination of K-52 (Grama-Tobosa Shrubsteppe) and K-53 (Trans-Pecos Shrub Savanna). Variant of SRM 734 (Mesquite-Oak). No biotic community in Brown et al. (1998): would be a Series under Warm Temperate Scrubland 133 or Warm Temperate Grassland 143. Edwards Plateau-Semiarid Edwards Plateau Ecoregion 30d (Griffith et al., 2004). Rocky Hills range site.

133. Stockton Plateau range- The Stockton Plateau comprises the westernmost and driest subdividion of the Edwrds Plateau. Range vegetation in this unit is primarily mixed prairie (this is in the Great Plains physiographic province), but there are affinities with the Rio Grande Plains to the south and east as well as the semidesert grassland and Chihuhuan Desert to the west in the Basin and Range physiogrphic province. This results in extremely species-rich range vegetation as was shown in this slide. Dominance is not obvious in this plant community and the phenomenon of aspect dominance creates a visual impression that tends to exaggerate shrub cover and composition. Some of the more common and diagonostic grass species included silver bluestem, little bluestem, sideoats grama, curly mesquite, buffalograss, fall witchgrass, blue grama, red grama, Texas cupgrass, and plains bristlegrass. Major shrubs included plateau live oak, guajillo, Roemer acacia, catclaw mimosa or wait-a-minute, sotol,Englemann pricklypear, littlleaf sumac as well as honey mesquite and Ashe juniper the latter two of which were remarkable limited on this range that approached the state of climax vegetation. Forbs, at least at this season, were limited and of little consequence. This slide detailed the physiogonomy and interior structure of this range type. Vegetation was a mixture of tall-, mid-, and shortgrass species (at least if grasses like little bluestem are viewed as tallgrass species) in addition to numerous shrub species. Physiogonomy was that of a predominately bunchgrass steppe with some of the sod-forming grasses like curly mesquite and buffalograss adding patches of closed grass canopy turf (ie. classic structure and diverse species composition of a mixed prairie). There were several layers (both herbaceous and woody) in this complex range plant community. Devil River Ranch, Val Verde County, Texas. May, a dry vernal aspect. FRES No. 33 (Southwestern Shrubsteppe Shrubland Ecosystem). Transition between or combination of K-52 (Grama-Tobosa Shrubsteppe) and K-53 (Trans-Pecos Shrub Savanna). Variant of SRM 734 (Mesquite-Oak). Brown et al. (1998) did not provide a biotic community for thei range vegetation: would be a Series under Warm Temperate Scrubland 133 or Warm Temperate Grassland 143. Edwards Plateau- Semiarid Edwards Plateau Ecoregion 30d (Griffith et al., 2004). Shallow Uplands range site.

134. The semiarid part of Edwards Plateau-The Stockton Plateau portion that joins the Trans Pecos portion of the Basin and Range physiographic province is a tough or hard kind of range. This variant of a Rocky Hills range site supported the dominant shrub catclaw or catclaw acacia (Acacia roemeriana), Juniperus species common to eastern and northern sections of the Edwards Plateau, and guayacan, a common woody component of the Rio Grande Brushlands. Grasses include silver bluestem, threeawns, and numerous Bouteloua species. Some authorities, including USDA ecosystem classifications, included parts of the Edwards Plateau along with the Rio Grande Plains as a shrub savanna. USDA followed this convention in FRES No. 32 (Texas Savanna Ecosystem), but based on the Kuchler map the FRES System designated the western, arid part of the Edwards Plateau as FRES No. 33 (Southwestern Shrubsteppe Shrubland Ecosystem). The predominant Kuchler unit is K-52 (Gramagrass-Tobosagrass Shrubsteppe), but there are elements of K-53 (Trans-Pecos Shrub Savanna) in this broad transition zone that is on the eastern edge of the Chihuhuan Desert and semidesert grassland cover types. Devil River Ranch, Val Verde County, Texas. SRM 734 (Mesquite-Oak) variant: the Edwards Plateau is a physiographic, not a vegetation-unit, but it is mapped as a vegetational area that encompasses woodlands, grasslands, and near-desert types. Edwards Plateau- Semiarid Edwards Plateau Ecoregion, 30d (Griffith et al., 2004).

135. Fall witchgrass (Leptoloma cognatum)- Fall witchgrass was just one of numerous species of perennial grasses on the mixed prairie-shrub savanna of the Stockton Plateau. Most of these grass species were displayed elsewhere in this on-line publication so this appeared a logicl location for this species that on some range sites in the Edwards Plateau responds as a decreaser. Panicoid grasses were much more limited than eragrostoid grasses on this range cover type. Fall witchgrass is a widely distributed species. This specimen was at peak bloom in the Western Cross Timbers. Tarleton State University Hunewell Ranch, Erath County, Texas. September.,

136. Catclaw mimosa or wait-a-minute (Mimosa biuncifera)- A leguminous shrub of wide distribution is catclaw mimosa. This shrub is found on range from central Texas westward to the deserts of southern California and far south into the deserts of Mexico.The vegetation shown in this slide was on a semidesert range in the foothills of the Bradshaw Mountains with catclaw mimosa present as a dominant shrub. Taken in conjuction with the preceding slides of range vegetation on the Stockton Plateau this rangeland scene illustrated the geographic range and local importance of M. biuncifera. Yavapai County, Arizona, June, full-bloom stage for catclaw mimosa.

137. Leader of catclaw mimosa or wait-a-minute and detail of inflorescences- The various Mimosa species are in the Mimosae tribe of the Mimosoideae subfamily of the Leguminosae. Some authorities elevated the three subfamilies of the Leguminosae (= Fabaceae) to the family taxon, but most plant taxonomists regard the legume, the fruit type in legmumes, as more important than the variation in flower types. Yavapai County, Arizona. June.

Organizational Note: Other examples of catclaw mimosa growing on semiarid Edwards Plateau savanna east of the Stockton Plateau and Chihuhuan Desert Regions were presented previously in this chapter with description and discussion of Juniper-Oak rangeland cover type (SRM 377) on which this shrubby legume is also abundant.

138. Basal parts of Texas sotol (Dasylirion texanum)- Leaves and flower stalk of Texas sotol. Devil River Ranch, Val Verde County, Texas. May.

139. Inflorescence of Texas sotol (and happy bees)- Flower stalk with immense cluster of flowers in Texas sotol. Devil River Ranch, Val Verde County, Texas. May.

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