6. White or pale death camas (Zigadenus elegans)- Pale death camas growing on a shaded hillside in the ponderosa pine forest of the Black Hills. This member of the lily family (Liliaceae) is one of about 11 Zigadenus species native to North America according to recent treatments (Burrows and Tyrl, 2001, ps. 787-792). All of these species should be regarded as toxic, but relatively few pose serious livestock poisoning hazards (Burrows and Tyrl, 2001, p. 790). Death camas is, however, one of the classic stock poisoning range plants and was included here for that purpose. White death camas has a large inflorescence that is quite conspicuous on the floor of the Black Hills ponderosa pine forest.

Students are referred to the classic text-reference by Kingsbury (1964, ps. 461-466) as well as the more recent and encyclopedic Burrows and Tyrl (2001).

Custer State Park, Custer County, South Dakota. July.

Ponderosa pine or western yellow pine is one of the most widely distributed Pinus species in North America, perhaps having the greatest latitudinal distribution of all. Ponderosa pine produces more timber than any other one Pinus species on the continent and it is second only to Douglas-fir in total annual lumber production (Harlow et al., 1979, p. 102). As implied by the common name of western yellow pine, P. ponderosa is in the yellow or hard pine subgenus of Diploxylon. There are three varieties of ponderosa pine: Pacific ponderosa pine (P. ponderosa var. ponderosa), Rocky Mountain ponderosa pine (P. ponderosa var. scopulorum), and Arizona ponderosa pine (P. ponderosa var. arizonica). Students can find details of the silvics of P. ponderosa in such standard texts and references as Harlow et al. (1979, ps.101-106) and Burns and Honkala (1990, Vol. 1, p. 413-424).

Importance of ponderosa pine from perspective of range cover types is as a dominant species that defines cover types, potential natural vegetation (eg. Kuchler mapping units), ecosystems, etc. There are more different forms or variants of understories in ponderosa pine forests than in most other forests or forest cover types, especially those that are defined on basis of dominance. (It was explained in the accompanying review of vegetation units that forest and rangeland cover types are dominance types.) In addition, ponderosa pine is a major (co-dominant to associate) species in forest types made up of several tree species (eg. Black Hills forest covered immediately above, California mixed conifer type, Pacific ponderosa pine-Douglas fir type, gannd fir type).

Within the general or greater region of the southern and central Rocky Mountains there are two ponderosa pine-defined forests that are potential natural vegetation according to the Kuchler system: K-17 (Pine-Douglas-Fir Forest) and K-18 (Arizona Pine Forest). These two Kuchler units plus K-10 (Western Ponderosa Forest), K-15 (Eastern Ponderosa Forest), and K-16 (Black Hills Pine Forest) were covered by Society of American Foresters as Interior Ponderosa Pine (SAF 237). Strictly speaking the ponderosa pine forest in central Arizona is in the Grand Canyon section of the Colorado Plateau physiographic province with specific examples shown from the San Francisco Mountains. The examples of ponderosa pine forest range in central New Mexico and Trans Pecos Texas were in the Sacramento section of the Basin and Range province (Sacramento Mountains and Guadalupe Mountains, respectively). The current publication arranged range-- both forest and rangeland-- cover types by general geographic or natural region and/or the somewhat smaller physiographic provinces within the former. As a result some cover types, especially some forest types, were included under more than one link category or, alternatively, "lumped"-- for convenience-- under a general category that was less specific and less precise. Ponderosa pine was one such example. Taxonomic unit of dominant species was interpreted as more important than physiographic province and section in defining a unit of vegetation (eg. range cover type). Such an arrangement was more consistent with the greater number of vegetation units by the Kuchler potential natural vegetation system than by the Society of American Foresters cover (= dominance) type system.

7. "East Meets West"- Unique ecotonal forest in Nebraska Sand Hills (also shown as Sandhills) near extreme northern edge (Pine Ridge Escarpment) of High Plains section of Great Plains physiographic province. Weaver (1965, p. 155) stated that the Pine Ridge Escarpment separated the High Plains on the south from the Missouri Plateau (to the north) section of the Great Plains. Range plant communities at such "unions" of landforms are generally "mixtures" of species from adjoining floristic provinces.

The unique vegetation in this photograph is a "three-way" ecotone of tallgrass prairie-eastern deciduous forest-ponderosa pine forest just above the Niobrara River on a bluff-like landform that resulted from wind-blown sand.The grassland community in the foreground was tallgrass prairie of little bluestem, big bluestem, needle-and-thread (Stipa comata), Indiangrass (Sorgastrum nutans), prairie sandreed (Calamovilfa longifolia), and plains lovegrass (Eragrostis trichoides). The largest conifers are of course ponderosa pine, representatives of the easternmost ponderosa pine forest in North America that is a part of the western forest regions. The other tree and shrub species are members of the deciduous forest formation of eastern North America. (Forest range types of this vast formation that are found in Nebraska were included at the end of the chapter designated Southern and Central Forests.) Species in the vegetation portrayed here that are part of the eastern deciduous forest region included eastern red cedar (Juniperus virginiana), shorter conifers at front edge of woody community, bur oak, eastern cottonwood, green ash (Fraxinus pennsylvanica), willow (Salix sp.), paper birch, quaking aspen, American or white elm (Ulmus americana), boxelder (Acer negundo), and eastern hophornbeam (Olstrya virginiana).

Fort Niobrara National Wildlife Refuge, Cherry County, Nebraska. Autumnal aspect, October. "Blend" of FRES No. 39 (Prairie Grassland Ecosytem), K-67 (Nebraska Sand Hills Prairie), SRM 601 (Bluestem Prairie) and FRES No. 21 (Ponderosa Pine Forest Ecosystem), K-15 (Eastern Ponderosa Forest), SAF 237 (Interior Ponderosa Pine). Northwestern Great Plains- Niobrara River Breaks Ecoregion, 43r (Chapman et al., 2001).

8. Landscape and vegetation of Pine Ridge Excarpment and Niobrara River of northern High Plains- Landscape scale view of tallgrass and mixed prairies and eastern ponderosa pine forest vegetation (background) and riparian vegetation (post-shedding of leaves) along Niobrara River (foreground). "Bird's-eye view" of the ecotonal vegetation shown in the preceding slide with tallgrass-mixed prairie grassland transition featured prominently between riparian zone and the eastern ponderosa pine forest in the background. There is also transitional vegetation between ponderosa pine forest and grassland that is a savanna of pines and prairie grasses. (This transition range type was covered as mixed prairie-ponderosa pine savanna under the chapter, Mixed Prairie, Grasslands.)

The small evergreen trees in the center grassland immediately beyond the riparian zone were invading eastern red cedar. Note that the deciduous woody vegetation also lined the draw that extended from the Niobrara River to the downhill edge of the ponderosa pine-dominated community.

Fort Niobrara National Wildlife Refuge, Cherry County, Nebraska. Autumnal aspect, October. "Blend" of FRES No. 39 (Prairie Grassland Ecosystem), K-67 (Nebraska Sand Hills Prairie), SRM 601 (Bluestem Prairie) and FRES No. 21 (Ponderosa Pine Forest Ecosystem), K-15 (Eastern Ponderosa Forest), SAF 237 (Interior Ponderosa Pine). Riparian vegetation was too small to be mapped at scale of these larger vegetation units, but it was certainly no less important. Northwestern Great Plains- Niobrara River Breaks Ecoregion, 43r (Chapman et al., 2001).

9. Eastern (Pine Ridge Escarpment) ponderosa pine forest- Interior of the open-- almost woodland-like physiogonomy-- form of ponderosa pine on the Great Plains at edge of Nebraska Sand Hills prairie. This vegetation could be interpreted as a mixed prairie grassland-western yellow pine forest transition (ie. a savanna of ponderosa pine and mixed or, even, tallgrass prairie; ecotonal vegetation between eastern edge of the western coniferous forest region and Great Plains grasslands). Equally valid in the mind of this author was the interpretation of regenerating ponderosa pine forest of the Pine Ridge Region as described by Weaver (1965, ps. 155-161). Weaver (1965, ps. 160-161) included the deciduous tree species of riparian areas and canyons as part of the regional evergreen forest of the Pine Ridge.

Soapweed yucca (Yucca glauca) growing atop the ridge in foreground and little bluestem (the brown bunchgrass) growing alongside the yucca and beneath pines were indicators of the Sand Hills prairie element that comprised the understorey of this vegetation.

This range vegetation was included as an example of the eastern form of ponderosa pine forest. FRES No. 21 (Ponderosa Pine Forest Ecosystem). K-15 (Eastern Ponderosa Forest). SAF 237 (Interior Ponderosa Pine). Fort Niobrara National Wildlife Refuge, Cherry County, Nebraska. Autumnal aspect, October.

Note: Background knowledge of the portion of the Great Plains province on which this range vegetation developed was in the definitive authority of Fenneman (1931, ps.17-21) and the exceptional bulletin by Trimble (1990, ps. 29-32). Northwestern Great Plains- Niobrara River Breaks Ecoregion, 43r (Chapman et al., 2001).

11. Southwestern Ponderosa Pine Forest- Texas is so big and and situated such as to be composed of seven (that is correct, 7) of the 29 biotic provinces of North America (Dice,  1943). These extend from the Austroriparian which includes the Pineywoods forests of east Texas through the Chihuhuan of the Trans Pecos Basin and Range physiographic province. Dice (1943, p. 41) extended a small portion of the Navahonian biotic province into the Guadalupe Mountains of the Trans Pecos region. Turner (1959, ps. 6-7) discussed the biotic province scheme of Dice but mapped the northern part, including the Guadalupe and neighboring ranges, of the Trans Pecos region as in the Rocky Mountain floristic province. In the Guadalupes there is a montane zone dominated by ponderosa pine with Douglas-fir on north slopes.

Note: Kuchler unit 17 included all ponderosa pine types in the southwest and the central Rocky Mountains whereas Kuchler separated out other ponderosa pine types such as Western Ponderosa Forest (K-10), Eastern Ponderosa Forest (15), Black Hills Forest (K-16), and Arizona Pine Forest (K-18). Obviously this is valid using overstory features (among others). It is also valid, however, to distinguish the ponderosa pine range types of the southern Rockys from those of the Colorado Rockys (to distinguish within K-17) on basis of different dominant grasses, forbs, and shrubs in the lower layers of understory.

15. Ponderosa pine-Arizona fescue (Festuca arizonica) range- An example of the physiogonomy and simple structure of the Arizona form of ponderosa pine forest with consociation of Arizona fescue as understorey. This was the three-needle fascicle Rocky Mountain ponderosa pine (P. ponderosa var. scopulorum) and not the five-needle fascicle Arizona ponderosa pine (P. ponderosa var. arizonica). Vegetation was of climax composition and structure, and proved that forest and range resources can be used wisely to produce renewable crops of forage, wildlife (and wildlife habitat), wood, and water.

Coconino National Forest, Coconino County, Arizona. Vernal aspect (June), but severe to exceptional drought so that phenological development of fescue was delayed. FRES No. 21 (Ponderosa Pine Forest Ecosystem). K-18 (Arizona Pine Forest). SAF 237 (Interior Ponderosa Pine), an Arizona variant. There was no SRM rangeland cover type designation for ponderosa pine forest range in any region except Pacific Northwest. SRM 110 (Ponderosa Pine-Grassland) is as close as possible (eg. Festuca idahoensis vs. F. arizonica as understorey dominant)-- and that is not close enough. Pinus ponderosa Association in Yellow Pine Series of Brown et al. (1998).

16. Structure and species composition of Arizona form of parklike ponderosa pine-Arizona fescue forest- This photograph showed the local (= micro-) topography or landform of a ponderosa pine forest cover type in the Colorado Plateau of central Arizona. There was adequate regeneration of pine to maintain the open, woodland-like forest stand. The understorey consisted of a single herbaceous layer composed almost exclusively of Arizona fescue (a consociation). At other locations (microsites, perhaps) the exclusive herbaceous understorey was a consociation of Stipa neomexicana (see below). In these single-species herbaceous layers there were scattered plants or, less commonly, local populations of blue grama. These did not seem adequate to warrent interpretation of blue grama as an associate species. Interestingly, mountain muhly (Muhlenbergia montana), which is often an associate or even co-dominant species of this range type, was not found in this vegetation. Cheatgrass (Bromus tectorum) grew in trace amounts, but this was restricted to road berms.

Coconino National Forest, Coconino County, Arizona. Vernal aspect, June (exceptional drought conditions). FRES No. 21 (Ponderosa Pine Forest Ecosystem). K-18 (Arizona Pine Fores). SAF 237 (Interior Ponderosa Pine), an Arizona variant. No SRM designation for this cover type. Pinus ponderosa Association in Yellow Pine Series of Brown et al. (1998).

17. Two "photo-plots" of Arizona form of Rocky Mountain ponderosa pine-Arizona fescue forest range- These two slides revealed a more diverse vegetation than that shown in preceding ones. Vegetation in these "photo-plots" (slides) included a few widely scattered shrubs. In the first slide a shrub element (if it could be called that) was represented by rubber rabbitbrush (Chrysothamnus nauseosus) in the far-right foreground. Immediately in front of the rabbitbrush was a local population of Stipa neomexicana. As shown below, this grass species also formed a single-species herbaceous layer in parts of this ponderosa pine forest. The rest of the understorey was composed of cespitose individuals of Arizona fescue (both green and brown-- still dormant-- tufts).

In the second slide, shrubs (but clearly not a shrub layer) were represented by a species of gooseberry (Ribes sp.) seen at left foreground. The woody plant behind and to the right of the gooseberry was a yound ponderosa pine. Students should observe (in both "photo-plots") that ponderosa pine consisted of several age classes, including small trees, indicating regeneration of this species.

Vegetation shown in these photographs was the natural potential of climax stage. Many of the larger pines had the form of old-growth specimens, but even if a few logs had been "snaked" out and the range grazed by livestock these were benchmark examples of virgin vegetation (and this vegetation was shown after four dry years that rated designation of exceptional drought).

Coconino National Forest, Coconino County, Arizona. June, vernal aspect (severe to exceptional drought). FRES No. 21 (Ponderosa Pine Forest Ecosystem). K-18 (Arizona Pine Forest). SAF 237 (Interior Ponderosa Pine), an Arizona variant. No SRM designation. Pinus ponderosa Association in Yellow Pine Series of Brown et al. (1998).

18. Arizona form of Rocky Mountain ponderosa pine-Arizona fescue forest range vegetation- In contrast to the parklike or woodland-like physiogonomy of the ponderosa pine-dominated community shown above (and below), some areas of this forest had more of a vegetational mosaic or patchwork. In this "photo-plot" a natural opening consisted of a "pure" stand of Arizona fescue while an adjoining patch was a stand of young ponderosa pine so dense that it's shade prevented growth of any species beneath it resulting in pine straw-covered ground and no understorey.

The igneous parent material of the soil was portrayed by the conspicuous boulders in foreground.

Coconino National Forest, Coconino County, Arizona. Vernal (and drought) aspect, June. FRES No. 21 (Ponderosa Pine Forest Ecosystem). K-18 (Arizona Pine Forest). SAF 237 (Interior Ponderosa Pine), an Arizona variant. No SRM recognition for this cover type. Pinus ponderosa Association in Yellow Pine Series of Brown et al. (1998).

Arizona ponderosa pine ranges have several species of grasses and shrubs which may either form biologically diverse understories of one to several layer(s) or, alternatively, "species sparse" understories consisting of a single-species stand or, at most, a few species. The single-species understorey examples of Arizona fescue and New Mexico feathergrass presented here were forms of parklike ponderosa pine forest. Other ponderosa pine forests have more biological diversity as both species-richness and structural complexity (more layers in the vegetation).

Coconino National Forest, Coconino County, Arizona. Estival aspect (but under conditions of exceptional drought), June. FRES No. 21 (Ponderosa Pine Forest Ecosystem). K-18 (Arizona Pine Forest). SAF (Interior Ponderosa Pine), another Arizona variant. No SRM designation. Pinus ponderosa Association in Yellow Pine Series of Brown et al. (1998).

Coconino National Forest, Coconino County, Arizona. Estival aspect, June

24. Specimens of New Mexico feathergrass (Stipa neomexicana) in ponderosa pine forest understorey- These robust plants were at seed-ripe or seed-shatter stage in a Rocky Mountain ponderosa pine parklike forest of the Arizona form. Exceptional drought conditions, but there had been enough soil moisture from winter precipitation for these cool-season natives to complete their annual growth cycle "with flying colors".

Coconino National Forest, Coconino County, Arizona. Beginning of dormant season for these denizens, June.

26. Grains of New Mexico feathergrass- Four ripe caryopses (each still enclosed within a palea and lemma, the latter of which has a sharp-tipped callus at base of a characteristically twisted awn) of S. neomexicana. These grains showed the potential for mechanical injury to grazing animals.

Coconino National Forest, Coconino County, Arizona. June.

27. Blue grama (Boutelous gracilis)- Blue grama was an associate of the dominant Arizona fescue and New Mexico feathergrass in the understorey of the Arizona form of ponderosa pine forest. Blue grama is one of the most widespred and important range plants in North America. In fact, if blue grama is second to anything in total acreage and forage production it is little bluestem. Blue grama retains it's nutritive value better in the dormant stage than most other grass species. It's culms and leaves sometimes remain in semi-dormancy which allows the plant to "green-up" and begin photosynthesizing more quickly than those species that have to initiate all new growth from the rootcrown. This is also a major reason why blue grama remains more nutritious during the dormant season. Blue grama is an eragrostoid grass (Eragrostoideae subfamily) rather than festucoid (Festucoideae subfamily) like Arizona fescue and New Mexico feathergrass.

Coconino National Forest, Coconino County, Arizona. Delayed estival aspect due to exceptional drought, June.

28. Slender wheatgrass (Agropyron trachycaulum)- This species is another festucoid grass that is sometimes a local dominant but it did not assume the overall dominance of Arizona fescue or New Mexico needlegrass (= feathergrass) in the understorey of the Arizona form of ponderosa pine forest.

Coconino National Forest, Coconino County, Arizona. Peak standing crop; grain in soft dough stage (June).

29. Red threeawn (Aristida longiseta)- Red threeawn is generally an invader on most range types and sites except for desert ranges where it may even be interpreted as a climax grass (eg. in the Sonoran Desert). In the understorey of ponderosa pine forest ranges red threeawn is a "black sheep" of the grass family compared to climax and productive forage species like Arizona fescue, New Mexico feathergrass, mountain muhly, and blue grama. This invader species is, however, of value as an indicator plant (indicative of disturbances including overgrazing) the high population of which serves as a warning to the range manager. The attractive specimens seen here were growing on-- and doing "their part" to stabilize-- a road cut during an exceptional drought (worst since Arizona began keeping records). They were valuable as both an indicator species and soil protector plus provider of relatively unpalatable forage.

Coconino National Forest, Coconino County, Arizona. June.

Vegetation of the ponderosa pine forests of southwestern North America as well as adjoining parts of the juniper-pinon woodland and mixed prairie grasslands commonly have shrub species, some of which provide substantial amounts of palatable browse and thereby serve as indicator species for ecological status of the range and degree of use. Many range plant communities of these cover types have a very limited shrub element and, frequently, no shrub layer (as in the Arizona examples of pristine Rocky Mountain ponderosa pine). Some shrubs are usually present however even if as minor members of the range vegetation. Browse produced by these woody species (thus the species themselves) is of more importance than suggested by "minority" status.

30. Cliffrose (Cowaina mexicana var. stansburiana)- Cliffrose, Mexican cliffrose, Stansbury cliffrose, or quninie-bush is one of the most valuable browse plants in the Colorado Plateau and mountains of the Basin and Range provinces. However it is rather limited within it's distributional range and it's brittle branches are easily broken which can result in low vigor or death of plants even under conditions of otherwise proper degree of use. Cliffrose is rated as good to excellent for browsing wildlife like deer but only fair to poor for cattle. Nonetheless, cliffrose is easily "browsed out" on livestock ranges where animal distribution is improper or inadequate. It was one of the major browse species drastically reduced by overstocking of range animals-- both livestock and wildlife-- during the early part of the Twentieth Century. In fact, the classic (and still controversial) study of grazing capacity and wildlife populations was that of the Kaibab Plateau range and deer herd of northern Arizona in the general area where these photographs of cliffrose were taken. (Students were referred to the abbreviated but readily available discussion by Humphrey [1962, ps. 138-142 passim].)

For general discussion of cliffrose the following timeless standards were recommended: Dayton (1931, ps 49-50), McMinn !1939, p. 204-205), Forest Service (1940, B68), and Sampson and Jespersen (1963, ps.85-87). Good summaries can be gotten from the various editions of North American Range Plants by Stubbendieck, Hatch, and others (1881, 1986, 1992, 1997).

The individuals of cliffrose shown here were mature-- rather old, actually-- specimens in the San Francisco Mountains in the Grand Canyon section of the Colorado Plateau. They were both blooming and bearing fruit. Coconino National Forest, Coconino County, Arizona.

31. Young plant of Mexican cliffrose- This young specimen was growing beside the larger plants shown in the preceding slides. It was not too young to have sexual reproduction. Coconino National Forest, Coconino County, Arizona. June.

32. Fruit-laden leaders of Stansbury cliffrose- Even after four years of the worst drought (rating of exceptional) in history of Arizona weather records the cliffrose plants presented here were flowering while bearing their newest fruit crop. Coconino National Forest, Coconino County, Arizona. June (and into a four-year exceptional drought awaiting summer rains).

33. Inflorescences and fruits of Mexican cliffrose (Cowaina mexicana var. stansburiana)- This species is in the Rosoideae (rose subfamily) of the Rosaceae the members of which have the classic rose hypanthium.The cliffrose fruit is an achene, a dry indehiscent fruit whose pericarp and testa (seed coat) are separate. Other genera of this subfamily that are major browse plants include Fallugia (eg. Apache plume), Cercocarpus (eg. the various mountain mahoganies), Rosa (the many wild roses), Rubus (blackberry, dewberry, raspberry), Purshia (antelope bitterbrush), and Adenostoma (chamise and red shanks). These various plants were discussed variously thoroughout this publication

Coconino National Forest, Coconino County, Arizona. June (into the fourth year of a drought rated as exceptional when this photograph was taken).

Note: Some authorities place this species in the Pursia genus as Pursia mexicana var. stansburiana. Mexican cliffrose does hybridize with the bitterbrush, P. tridentata var.glandulosa (= P. glandulosa).

34. Patch of Apache plume (Fallugia pradoxa)- Even under conditions of an extended (four years), exceptional drought (the worst; highest drought ranking) the native browse plant was "setting the woods afire" with it's colorful fruit. Yes, paradoxically it is the plumose fruits not inflorescences that appear to "bloom" in this valuable (for browse, erosion control, aesthetics, ecological indicator) range plant. Apache plume is generally ranked as fair (more-or-less) in browse rating, but in contrast to restricted species like cliffrose Apache plume is widely distributed and often locally abundant making it more valuable than indicated by it's browse rating.

Standard references again include Dayton (1931, ps. 50-51), McMinn (1939, p. 204), Forest Service (1940, B77), and Stubbendieck and Hatch with others (1981, 1986, 1992, 1997).

Coconino National Forest, Coconino County, Arizona. June.

35. Leaders of Apache plume laden with fruit- Close-in shot of the browse shown in the preceding photograph. The fruit is an achene. Coconino National Forest, Coconino County, Arizona. June.

36. Inflorescences of Apache plume- Stamen and hypanthia of flowers were visible even from this distance. Lincoln County, New Mexico. June.

37. Scrub live oak (Quercus turbinella)- Leaves and fruit (acorn) of one of the dominant scrub oaks (species of shrub oak) in the Arizona (= interior) chaparral and southern ponderosa pine forests. Twigs, leaves, and mast (acorns) of this shrub are valuable for browse (and concentrates in instance of acorns) for numerous species of range animals. For example both the Rio Grande and Merriam's subspecies of wild turkey (Meleagris gallopavo intermedia and M. gallopavo merriami, respectively) are found within the range of scrub live oak. Acorn mast is readily eaten by upland game birds, deer, cattle, and species of the pig group such javelina or collarded peccary (Tayassu tajacu= Dicotyles tajacu) as well as destructive feral hogs (Sus scrofa domestica).

38. Lightening-struck ponderosa pine- The ponderosa pine cover type is definitely a fire type. Volumes have been written about the role of fire-- both natural and anthropogenic-- in maintenance of these forest and range ecosystems. The historic fire regime was one on high frequency-low intensity such that commonly there was not a build-up of fuel and development of a fire staircase that allowed surface fires to develop into crown fires.

Lightening strikes are the main ignition source for natural forest fires. This mature ponderosa pine standing sentry atop the local high point bore the obvious mark of a direct hit by lightening that could have lead to a forest fire. Whatever fire conditions existed, whether any fire started by such ignition is a low-intensity surface fire or a holocaustic crown fire would depend on fuel. Even if the forest is as dry as the proverbial tenderbox climax ponderosa pine forests with grassy understories like those dominated by Arizona fescue and New Mexico feathergrass are much less likely to become "hell on earth" than those with numerous layers of vegetation leading staircase-like to the forest canopy.

This is the lesson of prescribed burning and proper grazing management on ponderosa pine ranges. Some grazing by livestock and/or big game species reduces buildup of vegetative material that can serve as fuel. Undergrazing of the forest understorey can contribute to destructive crown fires, but so can overgrazing. Prologued overuse that leads to range deterioration leaves the land with less cover as protection against soil erosion. Perhaps even more important in immediate outcome is weakening of the climax grasses which leaves them at a competitive disadvantage against woody plants. This results in increases in shrubs and trees which permits development of the fire staircase as well as leaving the soil surface with less herbaceous growth to break the impact of rain drops or hold back melt water. Understorey management is a key component in proper management-- including wise use-- of fire as a component of ponderosa pine ranges.

Looked at in this perspective, the more-dead-than-alive pine with the "blowed off" crown and the lightening blaze is "a thing of beauty".

Coconino National Forest, Coconino County, Arizona. June.

42. Rocky Mountain lodgepole pine forest- An exterior view of the Rocky Mountain form of the lodgepole pine range type showing details in structure of vegetation and plants (eg. retention of dead lower limbs on bole). This is the Rocky Mountain lodgepole pine (Pinus contorta var.latifolia). There was one prominent layer of woody plants (mostly shrubs; some, but rare, younger pines) and a less prominent layer of herbaceous species. The woody understorey was dominated by common juniper (Juniperus communis) with dwarf or broom huckleberry (Vaccinum scoparium) and myrtle huckleberry or blueberry (V. myrtillus subsp. oerophilum) as associate shrubs. Most common forbs were heart-shaped arnica (Arnica cordifolia) and one-sided wintergreen (Orthilia secunda). Grasses were absent, but there were a few "runt" individuals of Carex spp.

Apache National Forest, Grand County, Colorado. June. FRES No. 26 (Lodgepole Pine Forest Ecosystem). K-8 (Lodgepole Pine-Subalpine Forest). SAF 218 (Lodgepole Pine). Southern Rockies- Sedimentary Subalpine Forests Ecoregion, 21e (Chapman et al., 2006).

43. Rocky Mountain lodgepole pine forest- Interior veiw of the Rocky Mountain form of the lodgepole pine range (forest cover) type. There was a prominent understorey consisting of a woody (mostly shrub) layer and, less prominently, an herbaceous layer. Dominant shrub was common juniper with dwarf or broom huckleberry and myrtle huckleberry of secondary importance. The herbaceous layer (or understorey if one cares to view layer and understorey as synonymous) was mostly forbs with heart-leaved arnica and one-sided wintergreen most common. For practical purposes there were no grasses and very few stunted Carex plants.

Apache National Forest, Grand County, Colorado. June. FRES No. 26 (Lodgepole Pine Forest Ecosytem). K-8 (Lodgepole Pine-Subalpine Forest). SAF 218 (Lodgepole Pine). Southern Rockies- Sedimentary Subalpine Forests Ecoregion, 21e (Chapman et al., 2006).

47. Colony of fireweed or willowherb (Epilobium augustifolium= Chamaenerion augustifolium)- This member of the evening primrose family (Onagraceae) got it's more common common name from it's adaptation to fire, especially intense forest fires. Fireweed is a pioneer species-- usually the most prominent pioneer-- following fires. This perennial species is found in various regions of North America, but is most widely distributed in the general Rocky Mountain and Pacific Slope Regions.

Fireweed is especially valuable in watershed stability and protection following fires that denude steeply sloping land. It has been regarded as being of fair to good forage (when immature) for small ruminants. The showy, bright-pink inflorescences and graceful leaves impart aesthetic values to this forest and range forb as well.

Fireweed was one of the 200 range plant species included on the Master List for the International Range Plant Identification Contest sponsored by the Society for Range Management. The various editions of North American Range Plants (Stubbendieck et al., 1981, 1982, 1992, etc.) provided complete, yet concise, descriptions of E. augustifolium. Readers were referred to those excellent works. This species was also included in the Range Plant Handbook (Forest Service, 1941, p. W50) and Notes on Western Range Forbs (Hermann, 1966, ps. 185-186).

This robust clump was photographed in the understory of a mature lodgepole pine forest (elevation about 6000 feet) in Yellowstone National Park (and even before the 1988 holocaust). While fireweed is a pioneer and rapidly invades burnt-over ground it still persist into the climax forest as shown in this slide. July.

50. Landscape-scale view of Englemann spruce-subalpine fir forest- Appearance of this forest range cover type in early summer at the northern end of the Front Range of the Southern Rocky Mountains. This landscape photograph included the Subalpine and the Alpine life zone as generally used today. In the original life zone scheme (of seven zones) devised by C. Hart Merriam there was no Subalpine. Instead what is commonly called Subalpine in current usage was part or all of Merriam's Canadian and Hudsonian Zones. The Alpine, defined as being above timberline, is the same in both Merriam's and contemporary schemes.

There have also been differences in the use of Southern Rocky Mountains and Central or Middle Rocky Mountains. Fenneman (1931, ps. 92-182 passim) delineated the Southern Rocky Mountain physiographic province as extending through the Laramie Mountains of Wyoming while the Middle Rocky Mountain province included the Yellowstone Plateau, Bighorn Mountains, Tetons, Wasatch Mountains, and Unita Mountains, among others. Shelford (1963, ps. 160-181) divided the Central Rocky Mountains and the Southern Rocky Mountains differently from this. He included the Colorado Rockys as being in the Central division along with the Unita and Wasatch Ranges (Shelford, 1963, p. 160).

Either way this slide showed appearance of the Englemann spruce-subalpine forest cover type growing on the generic subalpine mountain zone inside the Front Range.

Larimer County, Colorado. June. FRES No. 23 (Fir-Spruce Forest Ecosystem). K-14 (Western Spruce-Fir Forest). SAF 206 (Englemann Spruce-Subalpine Fir). Englemann Spruce-Alpine Fir Series of Brown et al. (1998).Southern Rockies- Crystalline Subalpine Forests Ecoregion, 21b (Chapman et al., 2006).

51. Englemann spruce-subalpine fir forest- An exterior view of a stand of old-growth Englemann spruce- subalpine fir showing the physiogonomy and structure of this climax forest type. The Society of Amreican Foresters (Wenger, 1984, p. 3) ranked Englemann spruce as Tolerant and subalpine fir as Very Tolerant. The ecological veracity of these ratings was proven in this photograph. Both of these climax dominants were "reproducing in their own shade". The three distinctively green trees of shorter stature in the foreground were young Englemann spruce. Most of the shortest, smallest conifers with the distinctive bluish-green needles were Colorado blue spruce (Picea pungens), a species with tolerance rated as Intermediate. These blue spruce along with some subalpine fir were growing in openings recently created by fallen subalpine fir. Similar colored conifers in the midground between the foreground young trees and the old-growth conifers of the background were subalpine fir of somewhat older age and larger size.

The sparse understorey comprised primarily of Vaccinium species and was not shown in these exterior "shots" of this forest cover type.

Apache National Forest, Grand County, Colorado. June. FRES No.23 (Fir-Spruce Forest Ecosystem). K-14 (Western Spruce-Fir Forest). SAF 206 (Englemann Spruce-Subalpine Fir). Englemann Spruce-Alpine Fir Series of Brown et al. (1998). Southern Rockies- Sedimentary Subalpine Forests Ecoregion, 21e (Chapman et al., 2006).

52. Exterior view of a climax (and old-growth) Englemann spruce and subalpine fir forest in the Front Range of the Southern Rocky Mountains- Composite "shot" of a magnificant Rocky Mountain subalpine forest with a "picture-perfect" display of the species composition. The immense conifer on the far right margin was a subalpine fir as was the younger tree with the conspicuous grayish bark immediately to it's left and the smaller one to it's left. Note that the Very Tolerant subalpine fir were growing under shade of the Englemann spruce (the tall trees in the center and right-center background with the orangish- or reddish-brown trunks). Eyre (1980, p. 86) observed that while these two conifers were generally codominants there were areas and forest sites on which "subalpine fir is the major climax species" while Englemann spruce"is a persistent long-lived seral species". That was at least the partial apparent pattern shown here. Note also crown shape and dead limbs of the Englemann spruce patriarchs. Younger conifers in the left foreground were Englemann spruce indicating again successful regeneration of this Tolerant species. Regeneration of these two species beneath what were obviously old-growth individuals attested to the climax nature of this vegetation.

Understorey composition was primarily Vaccinium and Ribes species, some of which were shown below in this series of slides. Individual plants of Poa and Carex species were present in trace amounts.

Apache National Forest, Grand County, Colorado. June. FRES No. 23 (Fir-Spruce Forest Ecosystem). K-14 (Western Spruce-Fir Forest). SAF 206 (Englemann Spruce-Subalpine Fir). Englemann Spruce-Alpine Fir Series of Brown et al. (1998). Southern Rockies- Sedimentary Subalpine Forests Ecoregion, 21e (Chapman et al., 2006).

53. "Closer in" view of the right side of the preceding photograph- Regeneration of both Englemann spruce (larger of the saplings in right-of-center foreground and in left foreground) and subalpine fir (smallest foreground sapling to immediate left of the "big momma" parent subalpine fir.

Apache National Forest, Grand County, Colorado. June. FRES No. 23 (Fir-Spruce Forest Ecosystem). K-14 (Western Spruce-Fir Forest). SAF 206 (Englemann Spruce-Subalpine Fir). Englemann Spruce-Alpine Fir Series of Brown et al. (1998). Southern Rockies- Sedimentary Subalpine Forests Ecoregion, 21e (Chapman et al., 2006).

54. Colorado blue spruce in a sunlite opening in Englemann spruce-subalpine fir forest- This blue spruce was growing in an opening formed by a fallen subalpine fir in the forest in the three preceding photographs. Blue spruce is rated as Intermediate in tolerance. This species could regenerate in this climax forest only in microhabitats having more light than in the typical understorey environment of this old-growth forest.

Apache National Forest, Grand County, Colorado. June.

59. Whitestem, smooth or wine gooseberry (Ribes inerme)- Various Ribes species are found thoroughout the forests and adjoining general habitats of North America. Ribes is particularily well represented among the western coniferous forests. Dayton (1931, p. 40) reported that the widely distributed R. inerme displayed here was one of the most common, best known of the western gooseberries. Gooseberry and current are common names for the same or two closely related genera. Some authorities distinguished those plants of common name, gooseberry, as Grossularia species whereas those designated as currents were presented as Ribes species. Some authors have relied on as many as four genera for these plants. Currently, most authors lump all into Ribes. The common distinction between goosebery and current is that the latter bear few or no spines or prickles on their stems. More consistently, currents have jointed pedicels such that their fruit breaks off cleanly from this "stem" whereas the fruit of gooseberries remains attached to this pedicel thus necessitating "snipping" prior to making jams or pies (to which avid gooseberry pickers like your author can redily attest).

The nearly countless publications devoted to native plants (ranging from florae or manuals to field guides) have usually given good descriptions of these interesting shrubs. For their relevance and application to Forestry and Range Management the following classic treatments were recommended: Dayton (1931, p. 40-43) and Forest Service (1940, p. B130-B 133).

60. Flowering leader of whitestem, wine, or smooth gooseberry- This specimen grew adjacent to an Englemann spruce near Larimer Pass. The fruit of Ribes is a berry. It is often a valuable feed source for wildlife species including birds and rodents. Browse from Ribes species is of fair feed value for native ruminants.

An unfortunate turn of events combined with biological relationships led to reduction of Ribes species in regions renowned for the highly valued white pine species (Haploxylon subgenus of Pinus). Ribes serves as intermediate host for the accidentlly introduced white pine blister rust (Cronartium ribicola). In efforts to save the white or soft pines, especially western white pine (Pinus monticola), widespread Ribes eradication programs were conducted in efforts to control or, hopefully, eradicate the white pine blister rust. The effort was unsuccessful and preservation of white pines depends on breeding for rust-resistant genotypes. Fortunately Ribes species were not exterminated in an understandable but misdirected management practice. Ribes species suffer only minor damage when infected by C. rubicola.

Near Larimer Passs, Jackson County, Colorado. June.

61. Interior of a stand of old-growth Englemann spruce- The understorey of a virgin Englemann spruce forest with an exclusive ground layer of red-fruit gooseberry, false gooseberry, or cloudcap current (Ribes montigenum). Several of the Ribes species have "gobs" of common names. This species has proven to be somewhat confusing in that that is regarded as being in the Ribes group known as currents and, despite presence of prickles or spines, not in the gooseberry group that at times has been designated as the separate genus of Gossularia.

Readers should note regeneration of Englemann spruce, a species rated as Tolerant (Wenger, 1984, p. 3). This is an example of a "pure stand" of Englemann spruce. Eyre (1980, p. 86), citing other workers, specified that in the Englemann spruce-subalpine fir forest "pure stands of either species can be found". Such a stand was shown here.

Rocky Mountain National Park, Larimer County, Colorado. June. FRES No. 23 (Fir-Spruce Forest Ecosystem). K-14 (Western Spruce-Fir Forest). SAF 206 (Englemann Spruce-Subalpine Fir). Enlgemann Spruce-Alpine Fir Series of Brown et al. (1998). Southern Rockies- Crystalline Subalpine Forests Ecoregion, 21b (Chapman et al., 2006).

62. Englemann spruce-subalpine fir forest on shallow southeast slope- A marginal site for the Englemann spruce-subalpine fir cover type that is in a transition to a limber pine (Pinus flexilis) forest. This shallow site was an example of one kind of a subalpine forest in the Front Range of the Rocky Mountains just below timberline. Fir and spruce trees lacked the massive size of those in slides shown above on sites that were more favorable for development of the fir-spruce subalpine forest. Individuals of limber pine were abundant in this vegetation that was adjacent to a limber pine forest that was presented below. This marginal, transitional forest (ie. combination forest primarily of the Englemann spruce-subalpine fir cover type with components of the limber pine type) had a better developed and more species-rich understorey than many of the subalpine forests in the Southern Rocky Mountains. It was an example of of a Rocky Mountain subalpine forest range of the sort valuable for both livestock and wildlife, especially big game like elk and mule deer.

Rocky Mountain National Park, Larimer County, Colorado. Elevation roughly 10,000 feet. June. FRES No. 23 (Fir-Spruce Forest Ecosystem). K-14 (Western Spruce-Fir Forest). SAF 206 (Englemann Spruce-Subalpine Fir), but with scattered limber pines and conterminous with an old-growth stand of limber pine (SAF 219). Englemann Spruce-Alpine Fir Series of Brown et al. (1998). Southern Rockies- Crystalline Subalpine Forests Ecoregion, 21b (Chapman et al., 2006).

63. Understorey of Englemann spruce-subalpine fir on a shallow, rocky, southeast slope- Detail of the understorey of the subalpine transition forest shown immediately above. The understorey dominant was grouseberry or broom huckleberry (Vaccinium scoparium). Some species of bluegrass was (or where) present, but none had bloomed or set seed so the author could not identify it (them). One of the more common bluegrasses on such habitat is inland bluegrass (Poa interior). Muttongrass (P. fendleriana) is often locally dominant. The two large clumps of grass were the alien but naturalized orchardgrass (Dactylis glomerata) that served as yet another illustration as how pervasive many of the introduced or agronomic species have become through naturalization. The orchardgrass plant on the left was mostly hidden behind a clump of some species of Carex. Beidleman et al. (2000) described over 60 Carex species growing in Rocky Mountain National Park! Cones of both limber pine and Englemann spruce were visible in the photograph.

Rocky Mountain National Park, Larimer County, Colorado. Elevation about 10,000 feet. June. FRES No. 23 (Fir-Spruce Forest Ecosystem). K-14 (Western Spruce-Fir Forest). SAF 206 (Englemann Spruce-Subalpine Fir).

64. Population of grouseberry, grouse whortleberry, small-leaved huckleberry, dwarf huckleberry, or broom huckleberry (Vaccinium scoparium)- Members of the heath family are some of the most common understorey plants in mountain forests of western North America. Several Vaccinium species are understorey dominants or associates of the Englemann spruce-subalpine fir forest range cover type. V. scoparium is one of these that is valuable as browse for big game animals, sheep, and cattle as well as for it's fruit which is used by small animals like rodents and birds, uncluding upland game birds. Dayton (1931, p. 135) described this species as "... perhaps the most abundant and widespread as well as the smallest and smallest leaved of the western (so-called) huckleberry species".

This sample was in the understorey of the subalpine transition Englemann spruce-subalpine fir forest shown in the preceding two slides (a "sub-sample" of the understorey displayed in the preceding slide).

Rocky Mountain National Park, Larimer County, Colorado. Elevation about 10,000 feet. June.

69. Ecotone between subalpine fir-Englemann spruce forest and limber pine forest (or woodland)- These two photographs were of transitional forest vegetation contiguous with the Englemann spruce-subalpine forest containing considerable cover of limber pine (designated by the author as a "transition" between the two forest cover types or a "combination forest") discussed in the immediatley preceding four slides and the limber pine forest cover type displayed in the following four slides.

Ecotones are transitions or transition zones between two or more different plant communities. There are several forms of ecotones with various kinds of edges or borders. Of course, ecotones are themselves the overlapping borders of adjacent plant communities or vegetation types. Sometimes edges are sharp or discrete. Other forms of ecotones are more duffuse or "blended" over a wider space.

The forest community presented four slides back was one stage or one step in vegetation from Englemann spruce-subalpine fir forest to limber pine woodland. The vegetation seen in these two slides was the next spatial stage in this transition from spruce-fir forest to limber pine forest. This transition was largely a function of elevation and aspect in which limber pine became increasingly more abundant with increasting elevation and progression from a southeastern to a north slope. The forest community now presented was more of a true "mixture" of the two kinds of Rocky Mountain subalpine forest, two kinds of forest range.

It is important that students master the concept of ecotones (vegetational transition zones). Natural vegetation seldom grows in communities as discrete as populations of crops in farm fields or forest plantations.The vegetation displayed here was a good example of a forest ecotone (one in which elevation and slope were determining factors). Ecotones are one of the first examples that shows beginning students that Vegetation Science lacks the accuracy and precision of the physical-chemical sciences and engineering. Vegetation often comes comes in "shades of gray" when resource management demands (or appears to demand) a dichotomous choice.

The first slide showed some young Englemann spruce (eg. the rightmost foreground conifer and several of the spire-topped trees in the background) and common juniper (the small flat plants in the left foreground) intermixed with limber pine. The second slide had a higher proportion of limber pine. These were younger pines with open, widely branching crowns that grew on a south slope. These should be compared (contrasted) to the nearly naked, wind-pruned spires shown below (immediately following the next slide) in a pure limber pine stand on the north slope of this same mountain top. Common juniper was also present (and more conspicuous) in the second slide in the left foreground.

Rocky Mountain National Prk, Larimer County, Colorado. South slope (protected from dessicating, defoliating wind). Elevation about 10,500 feet. June. This ecotonal vegetational did not fit neatly into a simple "black or white" unit, but it was more of the limber pine cover type (SAF 219) whereas the preceding was more of the Englemann spruce-subalpine fir cover type (SAF 206). Southern Rockies- Crystalline Subalpine Forests Ecoregion, 21b (Chapman et al., 2006).

71. Limber pine forest or woodland- This was one of the most unique (and picturesque) forest range types found in the Rocky mountain cordillera. A woody plant-dominated community with erie, pole-like skeletons of ancient, wind-pruned limber pines formed an open upperstorey above a mixed understorey composed of a shrub layer and a pronounced herbaceous layer. This vegetation could be interpreted as either a forest or, given the open canopy of these wind-flagged trees, a woodland. Some authors have referred to this community as the limber pine woodland. It was entitled and described as a forest cover type by the Society of American Foresters (Eyre, 1980, ps. 98-99). The prominent shrubby and herbaceous layers of a browsable/grazable understorey made designation of forest range undeniable. Furthermore, it was permanent forest range.

The range component or feature of this vegetation is not limited to certain seral stages or to climax. Rather, there is a range resource throughout the entire sere (successional sequence) of vegetational development. Limber pine woodland is, however, the climax range vegetation on most forest sites on which it developed and persisted as subalpine forest, especially as krumholtz or elfinwood. Shelford (1963, p. 163) concluded: "Bristlecone or limber pine forms an edaphic climax on dry rocky slopes and windswept ridges".

On this north slope immediately below timberline, wind and wind-driven frozen precipitation (ice, sleet, snow) not only flagged the mature trees but killed back recent foliage on the lower brances of limber pine (eg. lower left foreground). Fallen dead trees so littered the ground that it was possible for man and beast to go from one to another without stepping on the ground. The short cool summers retarded microbial decomposition thereby allowing accumulation of limber pine logs among the slow-growing pines of younger generations and the slowly dying patriarchs of earlier cohorts.

The shrub layer was a combination of prostrate, wind-pruned limber pines as well as numerous kinds of willows and Vaccinium species like broom huckleberry or grouse whortleberry (displayed above). The herbaceous layer consisted of various species commonly found on the alpine elevations above the limber pine zone. Some of these were listed in the next caption and presented individually below.

Wind-polished trunks were on both dead and live limber pines (see succeeding slides also). Compare the flagged, almost krumholtz form of these limber pines growing on a north slope to those on the south side of this same mountain top that were shown in the three photographs immediately preceding the limber pine slide above.

Rocky Mountain National Park, Larimer County, Colorado. North slope. Elevation roughly 11,000 feet. June. FRES No. 26 (a complex of lodgepole, limber, bristlecone, and whitebark pine types). K-8 (Lodgepole Pine-Subalpine Forest). SAF 219 (Limber Pine). Bristlecone Pine-Limber Pine Series of Brown et al. (1998). Southern Rockies- Crystalline Subalpine Forests Ecoregion, 21b (Chapman et al., 2006).

72. Limber pine woodland range type- Physiogonomy, structure, and composition of a subalpine limber pine forest or woodland range cover type with well-developed herbaceous, shrub, and tree layers. Herbaceous species included bronze-scale sedge (Carex chalciolepis), blackroot sedge (C. elynoides), interior bluegrass (Poa interior), blackheaded daisy (Erigeron melanocephalus), and alpine clover (Trifolium dasyphyllum). Dominant shrubs were wind-hedged (one form of krumholtz) limber pines and willows of creeping habit due to wind-pruning and/or genetic morphology.

Two features worthy of note: Number one was that wind-scoured whitish bark was on both live pines as well as persistent in small patches on dead pines. Number two was abundant regeneration of limber pine which indicated that this forest or woodland of an Intolerant species was: 1) climax and 2) uneven-aged. Apparently this north slope habitat had at least two major or general impacts. There was more moisture from winter storms and the generally more mesic soil conditions of a north slope environment. There was also more wind which in winter was cold wind (either dry when "northers" came through or wet winds that drove frozen precipitation with force enough to defoliate and "flag" trees). Various combinations of these factors allowed an open canopy and wide spacing of adult limber pines which enabled germination and development of pine seedlings. The combined affect of wind-dessication and wind-driven ice and snow effectively pruned back crowns of mature pines enough to maintain an open forest floor. This in turn allowed reproduction of limber pine and development of a two- or even three-layered understorey. This understorey was comprised of young limber pines and willow species plus with many grasses, grasslike plants, and forbs common on the the alpine ecosystem above and adjoining this limber pine-dominated climax community.

Rocky Mountain National Park, Larimer County, Colorado. North slope. Elevation about 11,000 feet. June. No specific FRES: closest was FRES No. 26 (a complex of lodgepole, limber, bristlecone, and whitebark pine types). K-8 (Lodgepole Pine-Subalpine Forest). SAF 219 (Limber Pine). Bristlecone Pine-Limber Pine Series of Brown et al. (1998). Southern Rockies- Crystalline Subalpine Forests Ecoregion, 21b (Chapman et al., 2006).

73. Composite view of the limber pine forest range type- Structure and composition of a climax subalpine limber pine forest with the three prominent layers of tree, shrub, and herb distinct. Reproduction of limber pine was obvious. This indicated that crown cover and density of adult pines was low enough to permit regeneration of this Intolerant conifer. The uneven-aged structure (= presence of different crown classes) of the limber pine-- the dominant species-- population strongly suggested that this was climax vegetation. It was discussed in the preceding caption how wind had shaped (ie. pruned) the pine crowns thereby allowing establishment of seedlings of the Intolerant limber pine under the "shade" of their parent trees. Wind-burnished bark and dead wood was present on trunks of both living and dead limber pines. Mesic conditions afforded by the north slope on which this vegetation developed was also a requirement for regeneration of the Intolerant dominant.

Plant cover in the foreground was a composite sample of the shrub layer (= woody understorey) throughout this limber pine dominated-vegetation. The leftmost plant, shrub, in the foreground (to the right of the second boulder) was some species of willow that had a creeping habit due to either wind-sculpting and/or genotype (ie. an example of phenotypic plasticity and/or a combination of morphological plasticity and genetically determined shoot form). Willows (species and number of species was not determined) were the associate species of the woody understorey. The dominant of this shrub layer was wind-hedged limber pine (krumholtz or elfinwood form) such that the dominant of the tree or canopy layer, the overstorey, was also the dominant of the woody understorey (ie. limber pine dominated two of the three layers of this plant community). The krumholtz form of limber pine that dominated the shrub layer was represented by the P. flexilis plant(s) adjacent and immediately to the left of the creeping willow (note dead needles due to dessication by wind and wind-driven frozen precipitation).

It was possible that some of the limber pine component of the shrub layer was actually lower limb and branch portions (krumholtz form) of adult pines. Some adult pines of tree form may have developed elfinwood parts below their single, treelike bole that escaped wind-ice pruning and developed under apical dominance. Determination of such phenomenon would require close investigation, perhaps excavation of stumps and upper root systems. Nonetheless, there was unequivocal evidence of abundant sexual reproduction of limber pine in this stand.

Dominant species of the lowest layer of vascular plants, the herbaceous layer or understorey, was not obvious but was apparently blackroot sedge. Other common herb species were bronze-scale sedge, interior bluegrass (and other bluegrass species that were not blooming and could not be identified), composites like blackheaded daisy, and alpine clover. These herbaceous species were some of those most common on the alpine turfs and fell fields conterminous with the limber pine forest. A representative patch of this often turf-like herbaceous understorey was obvious immediately behind the krumholtz willow and limber pine in the foreground.

It was again remarked this climax plant community was permanent forest range: a grazable/browsable understorey was a component of this vegetation throughout the successional sequence of the sere and was not limited to seral stages prior to climax or canopy closure (whichever came first). Obviously the crown classes did not include the point of canopy closure. There was adequate light for understorey development and persistence throughout the entire spatial array of vegetation development.

Rocky Mountain National Park, Larimer County, Colorado. North slope. About 11,000 foot elevation. June. No specific FRES: closest was FRES No. 26 (a complex of lodgepole, limber, bristlecone, and whitebrk pine). K-8 (Lodgepole Pine-Subalpine Forest). SAF 219 (Limber Pine). Bristlecone Pine-Limber Pine Series of Brown et al. (1998). Southern Rockies- Crystalline Subalpine Forests Ecoregion, 21b (Chapman et al., 2006).

74. Limber pine forest cover type- Climax limber pine forest or woodland (depending on how crown canopy, aerial cover, tree spacing, and density, is interpreted) with a permanent grazable/browsable understorey. Structure and composition of this permanent forest range was evident in this slide. The were three prominent layers: tree, shrubby, and herbaceous. The herbaceous layer consisted of grass, grasslike plant, and forb species abundant of the alpine range ecosystem conterminous with this subalpine limber pine forest. Herb species included blackroot sedge (closest thing to the herbaceous dominant), bronze-scale sedge, bluegrass species, composites, and alpine clover.

The shrub layer was dominated by the wind-sculpted elfinwood form of limber pine with species of willow as associates. Interesting, the same species-- limber pine-- dominated two of the three layers of vascular plants in this vegetation. It was certainly the limber pine cover type.

Death of pine leaves by dessication on this wind-swept north slope was pronounced. Accumulation of dead and down timber of limber pine was due to slow rates of decomposition on this cold site. Even though the north slope aspect created a mesic site much of the annual precipitation comes as snow (or ice) when temperatures are too low for rapid rotting of wood and at this elevation the warm season is too short for much microbial reduction.

Rocky Mountain National Park, Larimer County, Colorado. North slope. Elevation approximately 11,000 feet. June. No specific FRES: closest was FRES No. 26 (a complex of lodgepole, limber, bristlecone, and whitebark pine types). K-8 (Lodgepole Pine-Subalpine Forest). SAF 219 (Limber Pine). Bristlecone Pine-Limber Pine Series of Brown et al. (1998). Southern Rockies- Crystalline Subalpine Forests Ecoregion, 21b (Chapman et al., 2006).

75. Blackroot sedge (Carex elynoides)- This cespitose sedge appeared to be the most common plant in the herbaceous layer of the limber pine woodland presented in the preceding five slides. The carices traditionally have not been accorded coverage like that of the more economically important grasses (or trees), but some outstanding references are available. For C. elynoides refer to Hermann (1970, ps. 204-205) and Hurd et al. (1998, ps. 108-109).

Rocky Mountain National Park, Larimer County, Colorado. North slope in understorey of limber pine woodland; roughly 11,000 foot elevation. June.

76. Bronze-edge sedge (Carex chalciolepis = C. heteroneura var. cahlciolepis )- This is a showy sedge (by sedge standards). It was both abundant and prominent in the understorey of the tract of limber pine woodland discussed above. Standard reference, including forage value, for this Carex species was Hermann (1970, p. 313-314).

Rocky Mountain National Park, Larimer County, Colorado. North slope in understorey of limber pine at about 11,000 feet. June.

78. Blackheaded daisy (Erigerion melanocephalus)- There are several species of Compositae in the alpine ecosystem and adjoining subalpine communities such as the limber pine forest. Blackheaded daisy was the most common forb in the tract of limber pine woodland presented above. Erigerion species are more commonly known as fleabanes. This species was not discussed in Notes on Western Range Forbs (Hermann, 1966), but can be found in standard references including field guides and florae.

Rocky Mountain, Larimer County, Colorado. North slope limber pine climax forest; elevation roughly 11,000 foot. June.