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One of the most extensive and important of the general range plant communities in the Nortrh American Western Range is the "Sagebrush Country". This apt (and poetic) designation includes expansive areas across parts of several geographical regions in which one or more Artemisia species to a large extent determine the physiognomy and structure of several prominent range dominance types in the grassland and shrubland biomes and are also important components of cover types in the forest/woodland biome. The entire generic"Sagebrush Range" is a discontinuous and diverse range plant community with several main "bodies" of sagebrush-dominated (sagebrush-defined is a more accurate description) vegetation and with "islands" of the same or similar range vegetation scattered among and within other range cover types.
This Artemisia-defined or -dominated vegetation extends from the sand sagebrush (Artemisia filifolia)-mixed prairie and sand sagebrush-sand shinery oak (Quercus havardii) in the Great Plains to the coast sagebrush (Artemisia californica) scrub along the Pacific Ocean with the vast big sagebrush (A. tridentata)-form of the Great Basin Desert and several smaller range types in between. Most of these Artemisia-defined communities have traditionally been described as shrublands or as scrub, either arid (deserts or desert-scrub like the Great Basin Desert) or semiarid (eg. Pacific coastal shrub). That convention seemed obvious so those range cover types were included under the Shrubland Biome grouping in the present publication.
Other Artemisia-defined vegetation is more accurately interpreted as a grassland with scattered sagebrush (where plants of an Artemisia species are "few and far between") as, for example, the sand sagebrush-sand bluestem (Andropogon hallii) prairie or, alternatively, as a savanna (where sagebrush density, cover, etc. is generally more than that of grassland and less than that of shrubland). Savanna quite properly describes the latter range plant community being, in the classic meaning, an ecotone or transition zone between grassland and shrubland (other savannahs are ecotones between forests and grasslands).
Savannahs have been accorded biome status the same as grasslands, shrublands, and forests. In this publication savannahs were shown in the Table of Contents as a biome (on equal standing with the other biotic communities), but the different savannas were treated variously under Forests, Shrublands, and Grasslands depending on whichever vegetational features (physiognomy, structure, growth form of dominants, or species composition) were most defiining or characterizing of the range plant community.
One of the major sagebrush-range communities in the Western Range Region is the one designated as sagebrush shrub steppe. This vegetation is a regional climax of big sagebrush (with other Artemisia shrub species dominant at smaller spatial scales) and perennial festucoid bunchgrassses. This vegetation is grassland, specifically steppe, "semi-arid grassland characterized by grasses occurring in scattered bunches with other herbaceous vegetation and occasional woody species" (Bedell, 1998). It is, however, a grassland of cespitose Gramineae (bunchgrasses) with shrubs numerous enough or having cover adequate to justify the modifer, "shrub". Shrub (in this case Artemisia species)- steppe is bunchgrass-dominated prairie with so much of a shrub component in the climax community as to require application of another group of range plant, of plant form, as an adjective to describe the vegetation adequately.
Sagebrush- bunchgrass steppe can be interpreted (at least visualized) as a broad ecotone between the big sagebrush- dominated Great Basin Desert and the festucoid, cespitose grass-comprised Palouse Prairie. The sagebrush-shrub steppe is a transition between desert (arid shrubland or scrub) and semiarid grassland. This shrub-bunchgrass range plant community is a savanna. Grassland, not shrubland, was the major biome. This range vegetation is shrub-steppe not grass-shrubland (even if the sagebrush steppe was listed under FRES designation of Sagebrush Shrubland Ecosystem). It followed that the sagebrush-bunchgrass steppe was placed under the grassland biome. Brown et al. (1998, p.40) distinguished between Great Basin Shrub-Grassland, the regional formation, within Cold Temperate Grassland, the climatic zone, (ie. a biotic community within a biotic province [Brown et al. 1998, p. 24]) which is the sagebrush shrub steppe and Great Basin Desertscrub, the regional formation or biotic community, within the Cold Temperate Desertland, the climatic zone or biotic province, which is the Great Basin Desert.
Given that the sagebrush-bunchgrass grassland has affinity with the sagebrush desert and the bunchgrass Palouse Prairie and that this shrub-steppe is a savanna between these two regional or zonal climaxes, there are range sites, habitat types, and range cover types in the Great Basin Desert and Palouse Prairie (and adjoining range plant communities) that closely resemble those in the shrub-steppe savanna. Some range dominance types in the Great Basin Desert seem to resemble dominance types in the sagebrush shrub-steppe more than other range cover types in the Great Basin Desert. The same is true for Palouse Prairie. In fact, there are "islands" or "outliers" of Palouse Prairie and of Great basin Desert in the ecotonal sagebrush shrub-steppe. These are generally topographic, edaphic, or local climatic climaxes within the general climatic climax (ie. polyclimaxes within the monoclimax). Examples include mesic grasslands on sheltered slopes at higher elevations and desert scrub on shallow, stoney, saline soils. Seral-stage vegetation on some range sites is sometimes about the same community as climax vegetation on another range site, habitat type, or, even, cover type. Distribution of plant communities-- at various spatial and temporal scales-- is typically discontinuous.
Vegetation will always be subject to interpretation and present some degree of arbitrariness or subjectivity. In the instance of sagebrush shrub-steppe where names and descriptions of rangeland cover types (Shiftlet, 1994) from two adjoining regions (say, Great Basin Cover Types and Northern Rocky Mountain Cover Types) are similar, choosing one or the other was of necessity judgmental on part of the one who photographed and described the range vegetation.
Contents for treatment of the sagebrush shrub-steppe came primarily from the large and vegetationally varied area of central and southeastern Oregon. This geographic area includes parts of both sagebrush shrub-steppe and cold desert scrub of the Great Basin Desert. Physical-chemical basis for distinction between these two regional plant communities (as between grassland and desert generally) is primarily climate, specifically the defining factor of precipitation (ie. semiaridity vs. aridity in the instance considered here). Direct basis for the difference in precipitation zones of this region is topography (= physiographic features). The Great Basin Desert is a rainshadow desert situated on the lee side of the great Sierra Nevada. The semiarid shrub steppe is also on the lee side of a mountain range, namely the Cascades, but this smaller, lower uplift is less effective at "wringing out" precipitation from moisture-laden air coming in from the Pacific Ocean.
Once more, physiographic provinces were critical to designating and distinguishing major units of range vegetation including range cover types, range sites, habitat types, etc. Other than for "islands" or "outliers" of vegetation that "strayed" out of their general region (from their regional or zonal climax) into an adjoining or neighboring regional climax as described above, the ecotonal sagebrush shrub steppe was in sections of the Columbia Plateau physiographic province while the Great Basin Desert communities were in sections of the Basin and Range physiographic province (Fenneman, 1931, ps. 225-273 and 326-395, respectively). These physiographic provinces are conterminuous at their respective southern and northern boundaries.
Plant communities and man's pedagogically designed units of vegetation quite obviously do not limit themselves to geographic units any more than to those of soil, slope, climate, etc., but the physiographic provinces and their sections provided meaningful patterns and furnished a rational framework from which to study range vegetation. This was true in particular for larger units of vegetation such as rangeland cover types (Shiflet, 1994).
After more than three decades, Natural Vegetation of Oregon and Washington (Franklin and Dyrness, 1973) remained the definitive source for range vegetation in the area from which the following examples of sagebrush shrub-steppe were drawn. The more recent Terrestrial Vegetation of California (Barbour and Major, 1995), the "vegetation bible" of California, also provided outstanding-- though, of necessity, brief-- coverage of the sagebrush steppe (Young et al. in Barbour and Major, 1995, ps. 763-796). Coverage of sagebrush steppe in California followed the format and nomenclature of the earlier Franklin and Dyrness (1973) treatment for sagebrush steppe conterminous in both states except that the sagebrush associations of Oregon were designated as sagebrush communities of California.
The Oregon Natural Heritage project recently released its Classification of Native Vegetation of Oregon (Kagan et al., 2004). This was based on the National Vegetation Classification System (Grossman et al. (1998) that was described and discussed elsewhere in the present publication. Common names of native vegetation associations as presented in Kagan et al. (2004) were given below following earlier designations of U.S.Forest Service ecosystems (FRES number and name) and Society for Range Management rangeland cover types (SRM number and name). Presentation of the common (vs. scientific) name of associations was done to be consistent with FRES and SRM units and to avoid the problem with ever-changing binomial names of plant species, many of which in Kagan (2004) were inconsistent with scientific names of genera and species in the seminal and historic literature including those by Kuchler (1964, 1966).
Franklin and Dyrness (1973, p. 6) provided physiographic and geologic provinces that differed slightly from the strict physiographic provinces of Fenneman (1931). Generally the Basin and Range provinces of both sources were the same. Franklin and Dyrness (1973, ps. 6) recognized High Lava Plains and Owyhee Upland provinces that coincided closely with the Payette section (Owyhee Mountains) and Harney section (including the Great Sandy Desert) of the Columbia Plateau province of Fenneman, 1931, ps. 244-248 and 272-273, respectively). The provinces of these two indispensible sources were specified from time to time in the captions below.
Various collequial names like "Oregon Desert", "High Desert", or "Oregon High Desert" have often been applied to the so-called Sagebrush Country that includes collectively the arid Basin and Range and semiarid Colorado Plateau provinces. Though such romantic and "catchy" appellations have been commonly and widely used and have been more-or-less effective in communicating a sense, spirit, or ambiance of this shrub-defined range area such terms are technically imprecise and somewhat misleading. They are even subject to misuse by special interest groups for political expediency. For that reason these appealing and long-used titles were avoided below. Even geologic-based titles appearing in technical references have been-- strictly speaking-- incorrect. Examples include parts or all of Big Sandy Desert (Fenneman, 1931, p. 226, 272-273) or Harney Digh Desert (Jaeger, 1957, p.148).
Such misnomer names, however, have been and, for that matter, remain useful in capturing the essence of the xeric nature of the semiarid environment of the shrub- steppe. Afterall, soils, slope, precipitation form and distribution, and numerous other factors interact with the precipitation zone so that annual quantity of precipitation is not always as important a factor as it might otherwise be. "The character of the Great Sandy Desert is not to be ascribed wholly to want of precipitation. This is, indeed, small but the aridity is intensified by the porous character of the mantle rock into which all surface waters disappear" (Fenneman, 1931, p. 273).
For general (and delightful) reading regarding range and the history of its use in this area two classics were cited as "required readings": Harney County, Oregon and its Range Land (Brimlow, 1951) and The Oregon Desert (Jackman and Long, 1964).
Big sagebrush-dominated (or -defined) range types- The most important of the sagebrush shrub-steppe communities are those recognized by the species and/or subspecies of big sagebrush that dominates the vegetation. The three major subspecies of big sagebrush that are most likely to be dominants on sagebrush steppe range are: 1) basin big sagebrush (Artemisis tridentata subsp. tridentata) on alluvial sites and those habitats generally having deeper, better-developed, and more fertile soils 2) Wyoming big sagebrush (A.tridentata subsp. wyomingensis) which is the most common and the one found on the greatest range of habitats and range sites, and 3) mountain big sagebrush (A. tridentata subsp. vaseyana) which is limited to mesic upland environments. Basin big sagebrush is typically the subspecies with the largest plants while Wyoming big sagebrush is the subspecies that usually has the smallest plants.
Big sagebrush-dominated range vegetation (both sagebrush steppe and sagebrush desert) has traditionally been identified, designated, and described based on which of these subspecies is the dominant of the range plant community. In some range vegetation there is more than one of these subspecies, but usually one is a farily clear dominant (although identification to subspecies taxon is not always obvious or an "easy call").
In some cases "dominance" is more a a matter of aspect dominance, the condition under which one or more plant species appear to dominate, present the appearance of dominance of, the vegetation due to brilliant floral display, large size as appearance against skyline, consistent distribution in the plant community, presence from year-to-year or season-to-season, etc. Dominance may not be determined or based strictly on the species that has (have) the greatest cover, density, frequency, etc.; largely determines the physiognomy; or most influences the range vegetation.
In theory, range cover (= dominance) types should be based on the strict meaning of dominance not aspect dominance, but when (and as long as) ecological descriptions are (remain) qualitative or descriptive rather than quantiative the phenomenon, the perspective, of aspect dominance is a possibility.
Of the three subspecies of big sagebrush Wyoming big sagebrush is the most common and often dominates the vast majority of sagebrush range. This is because it has has the widest adaptation to the varying habitats of the "Sagebrush Country" and due to the fact that much of the rangeland once dominated by basin big sagebrush has been converted to cropland.
Many of the published descriptions and community designations of big sagebrush-dominated vegetation do not specify subspecies. Value (even legitimacy) of distinguishing among the big sagebrush subspecies has been argued pro and con for a number of years. Such arguments seem likely to continue.
Franklin and Dyrness (1973, ps. 209-219, 223-225, 231-233, 234-242) provided names and descriptions of several big sagebrush-dominated or -defined associations and communities. These units of range vegetation were based on previous published work, personal communication, and original studies by the compiling authors. Nomenclature and discussion of big sagebrush-dominated communities by Young et al. in Barbour and Major (1995, ps. 771-775, 779-780) followed that of Franklin an Dyrness (1973). The presentation of big sagebrush-range communities below followed the treatment of Franklin and Dyrness (1973) and supplemented by Young et al. in Barbour and Major (1995) as well as (and as modified to conform with) the Society for Range Management rangeland cover types (Shiflet, 1974).
It was indicated periodically below that choosing between big sagebrush cover types included under Great Basin Cover Types and those under Northern Rocky Mountain Cover Types (Shiflet, 1994) was sometimes an arbitrary decision. Much of the central and eastern Oregon area that makes up the central part and much of the space of the sagebrush steppe is strictly speaking in neither the Great Basin (Basin and Range province) nor Northern Rocky Mountains but "sandwiched" in between.
Two of the major geographic regions supporting sagebrush shrub-steppe in North America are those generally defined by the physiographic provinces of 1) Basin and Range and 2) Columbia Plateau. Lines can be drawn on maps delineating these units, but native vegetation does not always honor those lines and commonly (and to the consternation of Man the Classifier) "overlaps" or crosses over the "property line" of physiographic provinces and their sections. To the extent t practicable big sagebrush-bunchgrass shrub-steppe was treated under separate headings and organizational arrangement according to these two divisions following the precident of Franklin and Dryness (1973) who devoted separate chapters to bunchgrass prairie (steppe) and shrub-bunchgrass savanna of the Columbia Plateau (Basin) and semiarid portions of Basin and Range (Chapters VIII and IX, respectively).
Treatment began with big sagebrush-bunchgrass steppe in the northern (semiarid; less xeric) part of Basin and Range.
1.Relict big sagebrush range- The bottom of this ancient drainage channel in the Payette section of the Columbia Plateau (Owyhee Upland) had a degree of protection from overgrazing by livestock afforded by rimrock-like walls. This range vegetation was largely subject only to natural grazing by native herbivores and thus served as a range reference area. Adjoining rangeland that had less natural protection had also received but limited livestock use and thus also served as relict range vegetation. (This did not imply that grazing by livestock is inherently damaging or that range grazed by livestock cannot also be relict vegetation. Protection from livestock use -- proper or improper-- does represent the natural state [pre-Columbian] of range use.)
The gray shrubs were Wyoming big sagebrush (Artemisia tridentata subsp. wyomingensis). Large individuals of bunchgrass was bluebunch wheatgrass (Agropyron spicatum). Idaho fescue (Festuca idahoensis), Sandberg bluegrass (Poa secunda= P. sandbergii), squirreltail bottlebrush (Sitanion hystrix), Junegrass (Koeleria cristata) were other native bunchgrass species present. There was also scattered plants of cheatgrass or downy brome (Bromus tectorum). Forbs were very sparse and limited mostly to native composites and spreading phlox (Phlox diffusa).
Other shrub species were gray rabbitbrush (Chyrsothamnus nauseosus) and green, Douglas, or viscid rabbitbrush (C. viscidiflorus).
Burns District, Bureau of Land Management, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 403 (Wyoming Big Sagebrush), generally and based on geographic location, but SRM 314 (Big Sagebrush-Bluebunch Wheatgrass) had some details that were more descriptive. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/Sandberg bluegrass/bluebunch wheatgrass association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
2. Epitome of big sagebrush-bluebunch wheatgrass- This relict vegetation was the Artemisia tridentata/Apropyron spicatum association that has been traditionally interpreted as the climatic climax of the Columbia Basin, High Lava Plains, and Owyhee Upland provinces of Franklin and Dyrness (1973, ps.211, 216-218, and esp. 236). In addition to the two dominants, Idaho fescue, Sandberg bluegrass, Junegrass, and green rabbitbrush were well-represented. Cheatgrass was almost totally absent from this relict site.
Burns District, Bureau of Land Management, Harney County, Oregon. June. Estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 403 (Wyoming Big Sagebrush), generally and based on geographic location, but SRM 314 (Big Sagebrush-BluebunchWheatgrass) had some details that were more descriptive. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/Sandberg bluegrass/bluebunch wheatgrass association of Kagan et al.(2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
3. Species composition of climax sagebrush shrub steppe- This "photo-plot" of the relict range vegetation presented in the two preceding photographs showed the rather limited botanical diversity of the climatic climax Artemisia tridentata/Agropyron spicatum association (Franklin and Dyrness, 1973, ps. 211, 216-218, and esp. 236). Wyoming big sagebrush and green rabbitbrush were featured in the foreground whereas a bluebunch wheatgrass consociation comprised the background. Other native cespitose grass species that were common in this pristine community included Idaho fescue, Junegrass, Sandberg bluegrass, and squirreltail bottlebrush. Gray rabbitbrush was present, but with less density and cover than was the case for green rabbitbrush. Cheatgrass was very limited, but present (as almost always).
Vegetation in this and the immediately preceding slide were just outside that growing in the natural drainage shown in the first slide of this section. The vegetation shown in these last two slides had undoubtedly been subjected to periodic overuse and, likely, overgrazing when this rangeland had been open range in the days of unregulated grazing on the Public Domain. In fact, adjudication in this entire area of public range (administered by the Bureau of Land Management) was an on-going legal range war through much of the 1950s.
Portions of this relict vegetation that had been subjected-- at least periodically-- to improper grazing management was an example of the power of recovery of this native vegetation. It was also a testament to the improved stewardship of the rangeland and of better working relations between a federal land agency and stockmen.
Owyhee Upland physiographic and geologic province of Franklin and Dyrness (1973, ps. 6, 34-38); Owyhee Mountains in Payette section of the Columbia Plateau physiographic province of Fenneman (1931, ps. 244-248).
Burns District, Bureau of Land Management. Harney County, Oregon. June. Estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 403 (Wyoming Big Sagebrush), generally and based on geographic location, but SRM 314 (Big Sagebrush-BluebunchWheatgrass) had some details that were more descriptive. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/Sandberg bluegrass/bluebunch wheatgrass association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
4. Picturesque example of species composition of basin big sagebrush-bluebunch wheatgrass range- This range plant community was the basin big sagebrush (Artemisia tridentata subsp. tridentata) form of the climatic climax Artemisia tridentata/Agropyron spicatum association (Franklin and Dyrness, 1973, 211, 216-218, and esp. 236). The large rocks were somewhat deceiving because this was a bottomland site in which the largest of the three subspecies of big sagebrush was the dominant shrub. Green rabbitbrush was the associate shrub. The dominant herbaceous species was bluebunch wheatgrass, but Sandberg bluegrass, Junegrass, squirreltail bottlebrush, needle-and-thread (Stipa comata), and Idaho fescue were common with the latter least abundant. Cheatgrass was present in smallest amounts of any grass species.
The largest specimen of basin big sagebrush was over six feet tall. There were several individuals of basin big sagebrush in the height range of four and a half to five feet.
For discussion of the various Artemisia species, including subspecies of big sagebrush, the timeless work of Beetle (1960) and the newer and outstanding field treatment by Wambolt and Frisina (2002) were recommended highly.
Burns District, Bureau of Land Management, Harney County, Oregon. June. Estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 401 (Basin Big Sagebrush), generally and based on geographic location, but SRM 314 (Big Sagebrush-Bluebunch Wheatgrass) had some details that were more descriptive. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/Sandberg bluegrass/bluebunch wheatgrass association of Kagan et al.(2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
5. Basin big sagebrush-bluebunch wheatgrass shrub-steppe- This example of the big sagebrush/bluebunch wheatgrass association had green rabbitbrush as the associate shrub and needle-and-thread as the associate herbaceous species. Sandberg bluegrass and Junegrass were also commonnly occurring native, perennial bunchgrasses. The naturalized annual cheatgrass was also present in trace amounts (the least plentiful grass). Forbs were almost as rare as cheatgrass.
Burns District, Burau of Land Management, Harney County, Oregon. June. Estival aspect. FRES No. 29 ). Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 401 (Basin Big Sagebrush), generally and baed on geographic location, but SRM 314 (Big Sabebrush-Bluebunch Wheatgrass) had some details that were more descriptive. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/Sandberg bluegrass/bluebunch wheatgrass association of Kagan et al.(2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
6. Detail of basin big sagebrush-bluebunch whaeatgrass range- Species composition and structure of the Artemisia tridentata/Agropyron spicatum association (Franklin and Dyrness, 1973, p. 236) on deep soil of a lowland habitat. Needle-and-thread was associate grass (herbaceous) species. In deeper soils, especially sandy soils, these two grass species "swap places" in dominance rank. A basin big sagebrush-needle-and-thread association was presneted below.
Burns District, Bureau of Land Management, harney County, Oregon. June. Estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 401 (Basin Big Sagebrush), generally and based on geographic location, but SRM 314 (Big Sagebrush-Bluebunch Wheatgrass) had some details that were more descriptive. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/Sandberg bluegrass/bluebunch wheatgrass association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
7. Basin big sagebrush/Idaho fescue-mixed bunchgrass range community- On this lower north slope there were several species of bunchgrasses, but mesic soil conditions favored Idaho fescue which was the predominant herbaceous species. This vegetation was best described as the Artemisia tridentata/Festuca idahoensis association (Franklin and Dyrness, 1973, ps. 211, 219-220, and esp. 239). Other locally important grasses included bluebunch wheatgrass, needle-and-thread, and squirreltail bottlebrush. Green rabbitbrush was the associate shrub species.
Drier upslope range vegetation was the big sagebrush-bluebunch wheatgrass association. The savanna vegetation of sagebrush bunchgrass steppe was a mosaic of polyclimaxes determined by complexes of soils, slope, aspect, elevation, etc. This quilt-like pattern included not only the big sagebrush associations but sites dominated by other Artemisia species including low sagebrush (A. arbuscula) and silver sagebrush (A. cana) associations.
This range was in the High Lava Plains province of Franklin and Dyrness (1973, p.6, 32-34) that corresponded to the Harney section (Big Sandy Desert) of the Columbia Plateau of Fenneman (1931, ps. 272-273).
Burns District, Bureau of Land Management, Harney County, Oregon. June. Estival aspect; major grass species were in the boot phenological stage. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 40l (Basin Big Sagebrush), generally and based on geographic location, but SRM 315 (Big Sagebrush-Idaho Fescue) has some details that were more descriptive. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/Idaho fescue association of Kagan et al.(2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
8. North slope basin big sagebrush/Idaho fescue vegetation- On this moist north slope Idaho fescue was the dominant of several bunchgrass speceies. Other major species were bluebunch wheatgrass, needle-and-thread, and squirreltail bottlebursh foremost grass in left-center of photograph). Franklin and Dyrness (1973, p. 238) cited findings by previous workers and concluded: "The Artemisia tridentata/Festuca idahoensis association is a topographic or topoedaphic climax on sites more mesic than those occupied by the Artemisia tridentata/Agropyron spicatum association".
On many of the sagebrush-bunchgrass ranges in the High Lava Plains province (Franklin and Dyrness, 1973, ps. 6, 32-34) vegetation is a "patchwork" of various climax communities (designated as associations by vegetation scientists). These mosaics of topographic, edaphic, climatic, etc. climaxes remain a textbook illustration of polyclimax theory applied to fairly large areas at relatively small spatial scale. Upslope vegetation in both this and the preceding slide was the big sagebrush-bluebunch wheatgrass association.
Burns District, Bureau of Land Management, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 401 (Basin Big Sagebrush), generally and based on geographic location, but SRM 315 (Big Sagebrush-Idaho Fescue) had some details that were more descriptive. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/Idaho fescue association of Kagan et al.(2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
9. Basin big sagebrush/needle-and-thread range type- The Artemisia tridetata/Stipa comata association is one associated with sandy soils (even those with deep sand) in both the High Lava Plains (as shown here) and Columbia Basin provinces (Franklin and Dyrness, 1973, ps. 224, 242). "The Artemisia tridentata/Stipa comata association is very similar to the Artemisia tridentata/Agropyron spicatum association physiognomically and floristically except for the substitution of Stipa for Agropyron" (Franklin and Dyrness, 1973, p. 224).
In the vegetation that developed on the sandy land habitat of this "photo-quadrant" bluebunch wheatgrass was the associate herbaceous species to needle-and-thread. Other grasses were limited with squirreltail bottlebrush ranking a distant third. The larger plants of basin big sagebrush were about five feet in height. Green rabbitbrush was the associate shrub. The lower-growing shrub with yellow flowers (right foreground) was sulfur or umberella wild buckwheat (Erigonum ubellatum).
The mosaic of several sagebrush range types (often designated as associations by plant ecologists) that developed in close proximity (often contiguous with each other) was described in the two immediately preceding captions. These spatial patterns of range plant communities were typically arranged as to topographic features like slope aspect (eg. north vs south slope), steepness or degree of slope, or position on slope (bottom, top, or middle of slope) or edaphic factors including soil texture, fertility, depth, or parent material.
In this polyclimax pattern of range vegetation many of the local plant communities were topographic, edaphic, or topoedaphic climaxes. The spatial relationship between the big sagebrush-bluebunch wheatgrass and the big sagebrush-needle-and-thread associations provided a case in point. These two climax communities typically occurred "cheek-by-jowl" with the two grass species shifting rank of dominant and associate depending on sandiness of soil (as was immediately obvious) and perhaps on numerous other factors (which were not readily obvious).
The basin big sagebrush-needle-and-thread association association could be visualized in the Clementsian monoclimax model as postclimax where big sagebrush/bluebunch wheatgrass is the climatic climax (Franklin and Dyrness, 1973, p. 236). Franklin and Dyrness (1973, p. 224) remarked that the big sagebrush/needle-and -thread association was found in both the Artemisia tridentata/Agropyron spicatum and Artemisia tridentata/Festuca idahoensis Zones (the climatic climaxes or zonal climaxes).
Burns District, Bureau of Land Management, Harney County, Oregon. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steeppe). SRM 401 (Basin Big Sagebrush), generally and based on geographic location, but a variant of SRM 314 (Big Sagebrush-Bluebunch Wheatgrass) was probably more descriptive in some details. Mixed Bunchgrass-Shrub Series of Brown et al. (1998).Basin big sagebrush/needle-and-thread association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
10. Interior of a basin big sagebrush/needle-and-thread range- Species composition and floristic arrangement of the Artemisia tridentata/Stipa comata association on a sandy soil was presented in this representative sample from the High Lava plains Province. The bunchgrasses were mostly needle-and-thread, the dominant herb, with some bluebunch wheatgrass, the associate herbaceous species. Other grasses were very limited with squirreltail bottlebrush being "second runner-up". Forbs were largely absent on this sandy soil.
High Lava Plains province of Franklin and Dyrness (1973, ps. 6, 32-34); Harney section (Big Sandy Desert) of Columbia Plateau physiographic province of Fenneman (1931, ps. 226, 272-273).
Burns District, Bureau of Land Management, Harney County, Oregon. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 401 (Basin Big Sagebrush), generally and based on geographic location, but a variant of SRM 314 (Big Sagebrush-Bluebunch Wheatgrass) was probably more descriptive in some details. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/needle-and-thread association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
11. Basin big sagebrush/basin or giant wildrye range- The Artemisia tridentata/Elymus cinereus association occurs in the High Lava Plains and Owyhee Upland provinces of eastern Oregon on more mesic bottomland habitats (Franklin and Dyrness, 1973, p, 235, 239). This range plant community has some of the highest potential productivity and forage yield capability of any of the big sagebrush types (subtypes, depending on the rangeman's view).
The particular example presented appeared generally to have been in some state of range degradation with only isolated "patches", such as the one shown here, at theoretical climax state. In local segments of this example range community basin or giant wildrye was the dominant range plant with its annual biomass production far outweighing that of any other species including the large subspecies of basin big sagebrush, the dominant shrub. Note size of basin wildrye compared to basin big sagebrush. The "photo-plot" preseented here had physiognomy that was typical for this rangeland type (subtype).
On the range shown here plant biodiversity was some of the highest among any of the sagebrush-defined range types. Bluebunch wheatgrass was the associate herbaceous species (due to greater cover and biomass of this species that was larger than any of the other subordinate Gramineae species). The latter inlcuded Idaho fescue, Junegrass, squirreltail bottlebrush, and Sandberg bluegrass among native cespitose perennials and the naturalized annual cheatgrass or downy bromegrass which was the most scarce of any grass. Needle-and-thread was rare to absent apparently having been replaced by Thurber needlegrass (Stipa thurberiana) on this less sandy and higher clay content soil.
Associate shrubs included both green or Douglas and gray rabbitbrush. Forbs were also high in both cover and density as well as number of species (by sagebrush shrub-steppe "standards"). These included tapertip hawksbeard (Crepis acuminata) and sulphur or umbrella wild buckwheat.
Burns District, Bureau of Land Management, Harney County, Oregon. June. Estival aspect; full-bloom phenololgical stage for most herbaceous species. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 401 (Basin Big Sagebrush), giant wildrye variant. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/basin wildrye association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
12. Basin or giant wildrye in a basin big sagebrush/basin wildrye association- Closer-in view of the range vegetation presented in the immediately preceding slide. A young plant of green rabbitbrush (far left margin of foreground) represneted one of the associate shrub species.
Floristic richness (= botanical diversity) in this sample of the Artemisia tridentata/Elymus cinereus association was illustrated in several succeeding slides. High Lava Plains province of Franklina nd Dyrness, 1973, p. 6, 32-34); Harney section (Big Sandy Desert) of the Columbia Plateau physiographic province of Fenneman, 1931, ps. 226, 272-273).
Burns District, Bureau of Land Management, Harney County, Oregon. June. Estival aspect; early bloom to anthesis phenological stage of giant wildrye. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 401 (Basin Big Sagebrush), basin wildrye variant. Basin big sagebrush/basin wildrye association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
13. Species diversity on basin big sagebrush/basin wildrye range- With but limited descriptions of the Artemisia tridentata/Elymus cinereus association as for example Franklin and Dyrness (1973, ps. 235, 239) it was not possible for this author to determine if the rich mixture of bunchgrass species encountered on the range presented in the two preceding photographs was typical for certain microsites of that range subtype or if such species mix represented some state of range deterioration. Franklin and Dyrness (1973, p. 239) reported succinctly: "Elymus cinereus is always conspicuous and sometimes dominates the ground cover". That was exactly the condition presented herein. Sometimes giant wildrye dominated; sometimes giant wildrye did not dominate and other typically decreaser grass species did.
In the photograph shown here the following native perennial bunchgrass species were present (approximate order of cover): bluebunch wheatgrass, Idaho fescue, squirreltail bottlebrush, Junegrass, and Sandberg bluegrass. Cheatgrass or downy brome, the Eurasian annual invader that dominates millions of acres throughout this region, was present only in trace amounts. Not visible in this "plot" but well-represented elsewhere was tapertip hawksbeard, a decreaser forb on most range sites.
Both green or Douglas and gray rabbitbrush were present. Basin and Wyoming big sagebrush were common depending on local or microsite. Basin big sagebrush grew in association with basin wildrye whereas Wyoming big sagebrush grew in affilitation with the other bunchgrass species on most local "spots" as shown here.
Burns District, Bureau of Land Management, Harney County, Oregon. June. Estival aspect; full-bloom phenological stage for perennial grasses. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush steppe). Variant of SRM 401 (Basin Big Sagebrush) overall, but with local communities of SRM 403 (Wyoming Big Sagebrush) such as the one shown for this caption. Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Basin big sagebrush/basin wildrye association of Kagan et al. (2004) overall, but locally Wyoming big sagebrush/bluebunch wheatgrass association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
14. Cast of cespitose characters- A local congregation of bunchgrasses on a microsite of a big sagebrush/basin wildrye range in the High Lava Plains province (Franklin and Dyrness, 1973, ps. 6, 32-34) included a range of species. These were squirreltail bottlebrush (large grass in right center foreground and small "clump" in left corner), Idaho fescue (left and center foreground), Junegrass (panicle visible behind and between left fescue plants), Sandberg bluegrass (right of and behind large squirreltail bottlebrush. Note absence of cheatgrass.
Several individuals of green rabbitbrush were visible in bakcground.
Burns District, Bureau of Land Management, Harney County, Oregon. June. Estival aspect; full-bloom phenological stage for grasses. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). Local variant of SRM 403 (Wyoming Big Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Overall, basin big sagebrush/basin wildrye association of Kagan et al. (2004), but locally basin big sagebrush/ Idaho fescue association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
15. Bird's eye-view of bunchgrass buddies- Idaho fescue and Junegrass on a microsite of big sagebrush/basin wildrye bottomland range. Good example of spatial pattern, arrangement of species, and plant community structure at microsite scale. A general idea of foliar and basal cover of plants and proportion of ground (soil surface) that is bare on sagebrush bunchgrass range in fairly high ecological statue (range condition class was probably low Good).
This example of sagebrush steppe was in High Lava Plains province of Franklin and Dyrness, 1973, ps. 6,32-34) that corresponded to Harney section of Columbia Plateau physiographic province of Fenneman, 1931, ps. 226, 272-273).
Bruns District, Bureau of Land Management, Harney County, Oregon. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). Local variant of SRM 403 (Wyoming Big Sagebrush). Mixed Bunchgrass Shrub Series of Brown et al. (1998). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
16. Tapertip hawksbeard (Crepis acuminata)- This generally highly palatable decreaser had a happy home in the herbaceous understorey of a basin big sagebrush-basin wildrye range of the general sagebrush shrub-steppe in the High Lava Plains province of southcentral Oregon.
Burns District, Bureau of Land Management, Harney County, Oregon. June.
17. Sulphur or umbrella wild buckwheat (Erigonum umbellatum)- There are several species of wild buckwheat in the forest, grasslands, and shrub steppe of the Cascades and Intermountain Region. Most of these species are fairly conspicuous when in flower. Some like this one are downright showy for their brief "moment of glory". (Put this professor in mind of "flowering" college coeds.) This individual was growing on the big sagebrush-basin wildrye range featured in the preceding slides. Colorful beggar ain't it?
Definitive treatment of the Erigonum species from the standpoint of range forbs remains that of Dayton (1960, ps. 65-72). According to this reference wild buckwheats are not particularily palatable, but sheep sometimes develop a fondness for the brightly colored flowers of sulfur buckwheat (must catch even the colorblind eye of a "bleating wooly").
Burns District, Bureau of Land Management, Harney County, Oregon. June.
18. Sandhills sagebrush shrub steppe- An example of the Artemisia tridentata/Chrysothamnus nauseosus-Stipa thurberiana association (Franklin and Dyrness, 1973, p. 242) was provided on a range with deep sand in higher hills of the Owyhee Upland (Franklin nd Dyrness, 1973, p. 6).
This Wyoming big sagebrush/green rabbitbrush-Thurber needlegrass range vegetation was interpreted by the author as another postclimax plant community much like the Stipa comata associations within the climatic or zonal climaxes of the Artemisia tridentata/Agropyron spicatum and Artemisia tridentata/Festuca idahoensis Zones (Franklin and Dyrness, 1973, p. 224). Alternatively this Thurber needlegrass association could be interpreted as an edaphic climax that was one of several polyclimax communities that develop along gradients of numerous interacting topographic and climatic factors.
Giant or basin wildrye was also conspicuous in this vegetation. Other abundant grasses included bluebunch wheatgrass, Idaho fescue, squirreltail bottlebrush, and Sandberg bluegrass. Commonness of Idaho fescue and basin wildrye, the two more mesic species, attested to this site's more favorable moisture regime (= the Clementsian chresard, term for soil water available for plant use).
Interestingly, the greater chresard was not reflected by occurrence of the more mesic basin big sagebrush rather than dominance by Wyoming big sagebrush. Franklin and Dyrness (1973, p. 224) cited earlier work that suggested low soil fertility rather than soil moisture was the main edaphic factor that accounted for dominance by Stipa comata in the Artemisia/Agropyron and Artemisia/Festuca Zones. These authors also reported, however, that there were differences in soil moisture equivalent as well as in fertility parameters such as cation exchange capacity among soils supporting these associations. Furthermore, the shrub associates were less sensitive to soil differences than were herbaceous plants (Franklin and Dyrness, 1973, p. 224).
Relative scarcity of the typically dominant big sagebrush and green rabbitbrush on this specific range was noteworthy. This vegetation was pristine. It was another example of relict vegetation that was valuable as a range reference area.
Vale District, Bureau of Land Management, Malheur County, Oregon. June. Estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). Thurber needlegrass variant of SRM 403 (Wyoming Big Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Wyoming big sagebrush/Thurber needlegrass association of Kagan et al. (2004). Northern Basin and Range- Dissected High Lava Plateau Ecoregion (Thorson et al., 2003).
19. Another version of sandhills sagebrush range (such as it was)- Wyoming big sagebrush and thickspike wheatgrass (Agropyron dasystachyum) were the dominant shrub and herbaceous species on this sand dune. Needle-and-thread was also present though in less abundance as was yellow wildrye (Elymus flavus) in even smaller amounts.
Apparantly there has been much less study and reporting of this sagebrush-grass community as none of the descriptions seemed to fit. Yet, presence of these species suggested that it was a distinctive range community and range site. It could have been in a severe state of range depletion, but the almost complete absence of cheatgrass except in small isolated populations and at much less cover than that of thickspike wheatgrass was incossistent with range retrogression in this area.
Rabbitbrush species were conspicuously rare in this vegetation.
High Lava Plains (Franklin and Dyrness, 1973, ps. 6, 32-34) corresponding closely to Harney section (Big Sandy Desert) of Columbia Plateau physiographic province (Fenneman, 1931, ps. 236, 272-273).
Deschutes County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). Variant of SRM 403 (Wyoming Big Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). None of the associations presented by Kagan et al. (2994) semed to fit. Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
20. Local colony of thickspike wheatgrass (Agropyron dasystachyum)- An example of thickspike wheatgrass on microsites of a sandhills Wyoming big sagebrush range.
Deschutes County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). Variant of SRM 403 (Wyoming Big Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
21. Thickspike wheatgrass- Basic form of a dominant member of the barley or wheat tribe on a sandhills Wyoming big sagebrush range. Spatial pattern of this grass species indicted presence of creeping rhizomes.
Deschutes County, Oregon. June.
22. Wyoming big sagebrush-green rabbitbrush range- These two views were of one form of the Artemisia tridentata-Chrysothamnus species association (Franklin and Dyrness, 1973, p. 242) of sagebrush steppe were in the High Lava Plains province (Franklin and Dyrness, 1973, ps. 3, 32-34), the Harney section (Big Sandy Desert) of the Columbia Plateau (Fenneman, 1931, ps. 236, 272-273). In addition to a diverse array of bunchgrasses (no apparent dominant grass species) and co-dominance of Wyoming big sagebrush and green or Douglas rabbitbrush this particular range had a floristically rich representation of forbs.
On most climax or high seral stage sagebrush shrub-steppe ranges forbs are in "short supply" compared to species and individuals of shrubs and grasses. This particular example of the big sagebrush-rabbitbrush association of sagebrush steppe had relatively high botanical biological diversity from the standpoint of species richness, "the diversity of species in a community measured as the number of species compared with the number of individuals in the community" (Allaby, 1998).
Bunchgrass species (again, the dominant grass species was not obvious) included: bluebunch wheatgrass, needle-and-thread, squirreltail bottlebrush, Idaho fescue, Junegrass, and Sandberg bluegrass. Some of the more common forbs were cushion or oval-leaf wild buchwheat (Erigonum ovalifolium; numerous larger forbs with showy off-white inflorescences), pale wallflower (Erysium occidentale), spread phlox (Phlox diffusa), and an unidentified Indian paintbrush (Castilleja sp.). Gray rabbitbrush was the associate shrub, but it ranked a "distant third" behind the co-dominant Wyoming big sagebrush and green rabbitbrush.
This range may have been degraded (abused to some degree of retrogression; depleted from natural potential), but, if so, deterioration was not severe because cheatgrass or downy borme and tansy mustard (Descurainia pinnata), two annual Eurasian weeds common on abused sagebrush ranges, were rare (no tansy mustard could be found) and no more common than on sagebrush steppe ranges that were in "mint condition" in this immediate area.
High Lava Plains province of Franklin and Dyrness (1973, ps. 6, 32-34); Harney section (Big Sandy Desert) of Columbia Plateau physiographic province of Fenneman (1931, ps. 236, 272-273).
Deschutes County, Oregon. June. Estival aspect. Phenological stages: peak bloom for most forbs, boot stage for most grasses, and pre-bloom for shrubs. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). Variant of SRM 403 (Wyoming Big Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
23. Green, Douglas, or viscid rabbitbrush (Chrysothamnus viscidiflorus)- This species and gray rabbitbrush (C. nauseosus) are typically the associate shrub(s) to the dominant big sagebrush (any of three major subspecies of Artemisia tridentata) on millions of acres across the vast Intermountain Region streatching from the West Slope of the Rocky Mountains to the Sierra Nevada-Cascades Ranges.The individual shown here represented the co-dominant species (with Wyoming big sagebrush) on the species-rich sagebrush steppe range shown in the immedaitely preceding two slides.
Deschutes County, Oregon. June.
24. Needle-and-thread (Stipa comata)- This was one of the more common grass species on the species-rich sagebrush shrub-steppe range featured above. On this range that provided an example of the Wyoming big sagebrush-green rabbitbrush association needla-and-thread and bluebunch wheatgrass were the grass species with the largest plants. Needle-and-thread was in the boot stage, the phenological stage in which the grass inflorescence is still enclosed within the enveloping sheath of the topmost leaf of the shoot.
Harney County, Oregon. June.
25. Cushion or oval-leaf wild buckwheat (Erigonum ovalifolium)- This Erigonum species was the dominant forb on the range presented above as an example of the Wyoming big sagebrush-green rabbitbrush association of sagebrush steppe. The wild buckwheats are some of the more numerous and frequently dominant forbs on the various sagebrush range cover types, including those dominated by big sagebrush and those dominated by Artemisia species besides A. tridentata.
Deschutes County, Oregon. June.
26. Pale wallflower (Erysium occidentale)- This biennial crucifer was one of the largest and more conspicuous forbs on the range featured above as an example of the Wyoming big sagebrush-green rabbitbrush association of sagebrush steppe. The biennial life cycle is far less common among range plants than are the annual and perennial life cycles. Biennialism is more common among forbs than grasses, grasslike plants, and woody species. On sagebrush shrub-steppe annual life cycles are most common among naturalized Eurasian grasses (eg. cheatgrass) and forbs (eg. tansy mustard).
The fruit of Cruciferae (Brassicaceae) members is a silique, a relatively short fruit (only two to three times as long as wide) which dehisces (splits) such tht the fuit walls fall off leaving a central parchment-like central partition, or, as in the case of this species, a silicle, elongated (more than three times longer than wide) pod-like fruit that splits lengthwise leaving a persistent partition when the fruit walls are shed.
Crucifer refers to the arrangement of petals in a shape resembling that of a cross.
Deschutes County, Oregon. June.
27. Spreading phlox (Phlox diffusa)- The Polemoniaceae (phlox family) is a small one but several members are conspicuous on grassland and savanna range communities in North America. These are more common in the spring flora. Spreading phlox is frequently common (often at local scale) on sagebrush steppe ranges. It seems to be more common on heavily grazed (especially overgrazed) ranges where it appears to be associated with Sandberg bluegrass. This species is not particularily palatable but certainly its low stature protects it from all but the most severe grazing defoliation.
Hermann (19, p. 234) remarked that Phlox species "are among the most showy plants of our western rangelands but are not imortant as forage".
This specimen grew on the forb-rich range presented above as an example of the Wyoming big sagebrush-green rabbitbrush association of sagebrush steppe.
Deschutes County, Oregon. June.
28. Two big sagebrush range types- In this landscape going from a narrow bottomland, a draw or wash with occasional runoff from showers and snowmelt, to rimrock there were two readily distinguishable range plant communities dominated by big sagebrush. A basin big sagebrush-green rabbitbrush association developed on the alluvial (wash) site in the foreground while a Wyoming big sagebrush/mixed bunchgrass community grew on the slopes and rimrock habitats above the wash community.
The herbaceous understories of both range communities had been severely depleted almost to point of elimination, but relict plants of bluebunch wheatgrass and Idaho fescue were found on the mesic, relatively deep soil of the alluvial site. Sandberg bluegrass was the most common native perennial grass on both range types. Cheatgrass, the naturalized Eurasian annual grass, was the most common herbaceous species on the alluvial site of the basin big sagebrush range type whereas cheatgrass, Sandberg bluegrass, and squirreltail bottlebrush seemed grow at roughly similar cover on the upslope Wyoming big sagebrush range type.
The hillside and rimrock were on a west-- therefore drier-- slope and more xeric soil moisture conditions contributed to a harsher environment so that Wyoming big sagebrush rather than the more moisture-requiring mountain big sagebrush (Artemisia tridentata subsp. vaseyana) dominated these habitats.
Harney County, Oregon. FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 401 (Basin Big Sagebrush), foreground; SRM 403 (Wyoming Big Sagebrush), background (hillside). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
Sagebrush-bunchgrass steppe developed throughout much of the Columbia Plateau as a unit of native vegetation distinct and different (in some respects) from that of the northern (semiarid) parts Basin and Range and Northern Rocky Mountains physiographic provinces. Given some areas of contact between Basin and Range and Columbia Plateau provinces it was not always possible to clearly distinguish between big sagebrush shrub-steppe range of these partially conterminous units, but an effort was made to do so to be consistent with the format of Franklin and Dryness (1973, Chapters VIII and IX) and correspond more closely to Level III Ecosystems.
29. Big sagebrush-bluebunch wheatgrass steppe- Landscape-scale view of the Artemisia tridentata/Agropyron spicatum zonal association, "the climatic climax in driest parts of the Columbia basin steppe region" (Franklin and Dryness, 1973, ps. 211, 216-218, esp. Fig. 155, p. 217). This photograph was of range vegetation in the Loess Islands portion of the Columbia Plateau not far from Grand Coulee and channeled scablands. Rangeland was of a generally more mesic nature (by climatic/edaphic standards of land in the Columbia Plateau) with a predominant north slope in background. Foreground was free of prevailing high slope, but of a southerly orientation. Range plant communities were described in captions that followed this landscape-scale perspective.
The range plant community introduced here and subsequently shown in detail in the following series of photographs was the Artemisia tridentata-Agropyron spicatum habitat type [that is apparently also the Artemisia tridentata-Agropyron spicatum association as one of nine zonal series] of Daubenmire (1968, ps. iii, 8-16). The Daubenmire habitat type classification was obviously the basis of the zonal association of Franklin and Dryness, 1973, cited immediately above[except for a" /" instead of a "-"]).
There were also local range plant communities of the Artemisia tridentata-Poa secunda (= P. sandbergii) zonal association (Franklin and Dryness, 1973, 211) or the Artemisia tridentata-Poa secunda habitat type of Daubenmire (1968, ps. iv, 62-64). One of these was presented near the end of this series of photographs.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin. Columbia Plateau- Loess Islands Ecoregion,10b (Environmental Protection Agency, undated).
30. Pristine big sagebrush-bluebunch wheatgrass steppe range- Range vegetation presented in this and the series of slides shown below was described and shown by Daubenmire (1968, esp. Fig. 4, p.10) as "in pristine condition". For being virgin this range vegetation was "boring", at least by standards of plant species richness, biodiversity, etc. (essentially numbers of plant species) because there was little else but basin big sagebrush and bludbunch wheatgrass from obvious cover, density, biomass, etc. Other species included: both needle-and-thread (Stipa comata) and, lesser amounts, western or Nelson's needlegrass (Stipa occidentalis var. nelsonii= S. nelsonii), Sandberg's bluegrass, Idaho fescue, cheatgrass or downy brome among grasses; some species of balsamroot (Balsamorhiza sp?) and threadleaf fleabane (Erigeron filifolius) as about only forbs; and spiny hopsage (Grayia spinosa= Atriplex spinosa) the only other shrub of note except for basin big sagebrush. The photographer did not find any representatives of rabbitbrush (Chrysothamnus spp.), but it would be easy to overlook a few in this "sea of sagebrush" and it couldprobably be safely assumed that there was some rabbitbrush present.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass). Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin. Columbia Plateau- Loess Islands Ecoregion,10b (Environmental Protection Agency, undated).
31.Virgin shrub-steppe- Closer-in views of virgin vegetation of a basin big sagebrush-bluebunch wheatgrass shrub-steppe range. The two dominants were about the only species that were conspicuous in these photographs, except for the "stand-out" plant of spiny hopsage in the second of these two photographs (right corner foreground). Several plants of needle-and-thread at grain shatter stage were featured prominently in foreground of the first slide, but this was not visible after Jpegging and scanning (unless one has a vivid imagination). Some Sandberg's bluegrass was present in left foreground (shadows) of second slide.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass). Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin. Columbia Plateau- Loess Islands Ecoregion,10b (Environmental Protection Agency, undated).
32. Textbook- Classic representation of physiogonomy, structure, and species composition of basin big sagebrush-bluebunch wheatgrass shrub steppe range shown to good advantage in an upslope view. Relief of the land was also typical of the "up-and-down" rolling sweep pattern of the Loess Islands. Range plant species present (thought most not discernable) in addition to the two dominants included: both needle-and-thread and, less abundant, Nelson's or western needlegrass, Sandberg's bluegrass, Idaho fescue, cheatgrass, some species of balsamroot (Balsamorhiza sp?), threadleaf fleabane, and spiny hopsage.
The fact that big sagebrush-bunchgrass (including numerous species of cespitose grasses) shrub-steppe is a svaanna was portrayed more obviously in this and the next (immediately following) two photographs. At zonal scale the sagebrush (including several Artemisia spp.)-bunchgrass shrub steppe is an ecotone--a transition zone--between the sagebrush (especially big sagebrush) scrub or shrubland, desert range types, and bunchgrass prairie (think Palouse Prairie), grassland range types.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass). Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin. Columbia Plateau- Loess Islands Ecoregion,10b (Environmental Protection Agency, undated).
33. Interior of basin big sagebrush-bluebunch wheatgrass shrub-steppe range- Two views of sagebrush-bunchgrass steppe "from the inside looking out". From this perspective, plants of basin big sagebrush figure more prominently in physiogonomy and structure of this Columbia Plateau savanna. It was worth repeating from the preceding photo-caption that this savannah is a transition zone--an ecotone--between the zonal range vegetation of sagebrush desert and zonal range plant communities of bunchgrass prairie or steppe, a grassland formation or subformation (depending on which classifiction scheme one follows).
.In addition to conspicuous basin big sagebrush and bluebunch wheatgrass other range plant species encountered by the photographer were needle-and-thread and, less abundant, Nelson's or western needlegrass, Sandberg's bluegrass, cheatgrass, Idaho fescue, some species of balsamroot (Balsamorhiza sp?), which along with its composite "cousin" threadleaf fleabane, were about the only forbs present. The other shrub on this range was spiny hopsage. The author could not find any rabbitbrush, but it had to be assumed there was some present.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass). Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin. Columbia Plateau- Loess Islands Ecoregion,10b (Environmental Protection Agency, undated).
34. Deeper in the interior- Structure and species composition of the basin big sagebrush-bluebunch wheatgrsss shrub-steppe presented above was featured in this photo-quadrant. In addition to basin big sagebrush and bluebunch wheatgrass other plant species descernible were needle-and-thread (at immediate post grain-shatter stage), Sandberg's bluegrass, one plant of threadleaf fleabane, and one representative of the Eurasian nautralized weed, western or yellow salsify (Tragopogon dubius) at late pre-bloom stage (swollen upper shoot).
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass).Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin. Columbia Plateau- Loess Islands Ecoregion,10b (Environmental Protection Agency, undated).
35. Deeper yet in the interior- Another photo-quadrant near large big sagebrush plant "landed" these two nice specimens of arrowleaf balsamroot (Balasmorhizza sagittata). These plants were handily identified by the characteristically shaped leaves. This was not always an option when dealing with Balasmorhizza species (see very next photograph and caption). Also present amount the counted were several plants of basin big sagebrush and a lot of Sandberg'sbluegrass.
Douglas County, Washington. June (early summer).
36. Two denizens of the basin big sagebrush-bluebunch wheatgrass- These two range pals of the herbaceous layers of a basin big sagebrush-bluebunch wheatgrass shrub-steppe were bluebunch wheatgrass (left) and Carey's balsamroot (Balasmorhizza careyana) or rosy balsamroot (B. rosea) or a hybrid thereof (B. careyana X B. rosea). There are also reports of hybrids of B. sagittata and B. rosea (Flora of North America Editoriaol Committee, Vol. 21, ps. 95, 96). On this same range, this species (or hybrid) and the more common and better-known arrowleaf balsamroot (Balasmorhizza sagittata), that was presented in the immediately preceding slide, sometimes grew within a few feet of each other. Positive identification of the species (or hybrid) of this balsamroot was not possible given the post-bloom and fruit-shatter state of specimens.
Other range plants present included part of one basin big sagebrush and cheatgrass (at the stage of disintegration).
Douglas County, Washington. June (early summer).
37.Western or Nelson's or, maybe even, Columbia needlegrass (Stipa occidentalis var. nelsonii= S. nelsonii)- There are a number of Stipa species throughout the Intermountain West of North America-- at least there numerous Stipa species before this traditional genus was " split nine ways to Sunday" by revisionist taxonomists as treated, for example, in Flora of North America- (Vol. 24)...Poaceae, part 1 (Barkworth et al., 2007). Readers should this comprehensive text (and its older sister volume 25) for latest taxonomic treatment. The author of Range Types of North America elected to stay--to the extent--with traditional scientific names found in the classic works on range vegetation and/or in the flora or manual covering the area, region, state, etc. in which range plants were photographed. Hence, by way of example, the binominial Stipa occidentalis var. nelsonii was retained with regard to western needlegrass presnted here because that was the scientific name used in Flora of the Pacific Northwest (Hitchcock and Cronquist, 1973, p.672) as well as other standard works like the readily available description of Palouse Prairie by Dodd in Grass Systematics (Gould and Shaw, 1983, p. 353).
Some of the varieties of S. occidentalis (Hitchcock and Cronquist, 1973, p.672) were at one point in taxonomic time given species status or as a variety of S. columbiana. This included S. nelsonii (which following that was S. columbiana var nelsoni in Hitchcock and Chase [1950, p. 458]), S. californica, and S. viridula var. pubescens, and S. viridula var. minor which, again, were included as varieties under S. occidentalis by Hitchcock and Cronquist, 1973, p. 672). Barkworth et al. (2007, ps. 121-125) reinterpreted S. occidentalis var. californica and S. occidentalis var. pubescens of Hitchcock and Cronquist (1973, p. 672) as Achnatherum occidentale subsp. californicum and A. occidentale subsp. pubescens, respectively. Barkworth et al. (2007, ps. 123-124) elevated S. occidentalis var. nelsonii back to species level as A. nelsonii (ie. predating Hitchcock and Chase [1950, p. 458]). Barkworth et al. (2007, ps. 1213-124) thereupon split A. nelsonii into A. nelsonii subsp. nelsonii and A. nelsonii subsp. dorei. Somewhere along the way Stipa or Achnatherum nelsonii picked up a second "i" to accompany its restored status as a species.
So is the common name of this species properly designated as Columbia, western or Nelson's needlegrass? (Sherlock Holmes could probably--would you believe, maybe-- solve this mystery of moving taxa, but he would be wise enough not to waste his time.)
The inflorescence type of the Stipa species is a panicle. The panicle of S. occidentalis var. nelsonii is a narrower semi-contracted panicle than is the case for many members of this traditional genus. This author strongly recommended and referred readers to Barkworth et al. (2007, p. 122) as an outstanding reference---for line drawings of the species (by whatever scientific name was used in this revolutionary treatment).
Okanogan County, Washington. June (early summer). Immediate floret-shedding stage.
38. Basin big sagebrush (Artemisia tridentata subsp. or var. tridentata)- Large specimen of basin big sagebrush in the virgin vegetation of the basin big sagebrush-bluebunch wheatgrass range described above. The various taxa within A. tridentata remain a source of some confusion (even after having recognized the thhree or four subspecies or varieties decades ago). One of the more useful (and straightforward) treatments was that of Roche (1983, ps. 145,147). The specimen shown here fit "textbook" features, namely a single large and round bole (trunk like that of a small tree) and the largest limbs (fork of the trunk) were only two (two or less is the rule). See Beetle (1960, ps. 36, 38, esp. plate 8, p. 50). The general large size of this rascal was a sagebrush spotter's first clue that it was A. tridentata subsp. tridentata. Besides Beetle (1960) another outstanding guide to sagebrush was Wambolt and Frisina (2002).
Douglas County, Washington. June (early summer).
39. Crown of the sagebrush-bunchgrass shrub-steppe- The highest layer of this shrub-grass savannah was not exactly a canopy or crown layer, but basin big sagebrush did have the highest level of range vegetation to itself. A crown that is not somewhat level but instead has a center (or even a side) that is higher than other parts (perimeter, especially) is characteristic of basin big sagebrush (Roche, 1983,p. 147).
Douglas County, Washington. June (early summer).
40. Spiny hopsage (Grayia spinosa= Atriplex spinosa)- Spiny hopsage is one of several shrub species of the Artemisia tridentata-Agropyron spicatum habitat type. Other shrubs include both green and rubber rabbitbrush, gray or spineless horsebrush (Tetradymia canescens), and three tip or cutleaf sagebrush (Artemisia tripartita) (Daubenmire, 1968, ps. iii, 8-16; Franklin and Dryness, 1973, ps.215, 216). Specimens viewed here were growing in the basin big sagebrush-bluebunch wheatgrass shrub-steppe range described above.
Douglas County, Washington. June (early summer).
41.Threadleaf fleabane (Erigeron filifolius)- There are numerous Erigeron species (depending on author and "lumper"vs. "splitter" tendencies) in the "sagebrush country" ofthe Columbia Plateau, but this is one of the more common ones. It was growing on the pristine basin big sagebrush-bluebunch wheatgrass ahrub-steppe range covered above.
Douglas County, Washington. June (early summer).
42.A little different "version"of the basin big sagebrush-bunchgrass steppe- On the pristine big sagebrush-bluebunch wheatgrass range featured in this series of slides there were local range plant communities that were of the Artemisia tridentata-Poa secunda habitat type of Daubenmire (1968, ps. iv, 62-64). These local units of range vegetation were minor on the range featured here, but the one shown here was a good example of this vegetational classification unit. Daubenmire (1968, ps.62-64) did not know how to interpret this habitat type. It was not a degraded form or phase of the Artemisia tridentata-Agropyron spicatum habitat type because there were ecotones between these two habitat types. Furthermore, cheatgrass (the key or characteristic indicator species of range deterioration on both steppe and sagebrush-steppe) was typically limited to almost absent on this habitat type. Note near absence of cheatgrass on the example shown here.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). No SRM (would have to be a Big Sagebrush-Sandberg Bluestem). Artemisia tridentata-Poa secunda habitat type (Daubenmire, 1968,ps.iii, 8-16). There was not an appropriate Series in Brown et al. (1998), but this would be Columbia Plateau- Bluegrass-Shrub Series. Columbia Plateau- Loess Islands Ecoregion,10b (Environmental Protection Agency, undated).
43. Down the to the big draw (or in a coulee into the coulee)- View from the predominately north slope basin big sagebrush-bluebunch wheatgrass shrub-steppe range that was covered in detail immediately above looking down into valley of Grand Coulee. Another example of the climatic climax Artemisia tridentata/Agropyron spicatum zonal association (Franklin and Dryness, 1973, ps. 211) which was the orignial Artemisia tridentata-Agropyron spicatum habitat type described by Daubenmire (1968,ps.iii, 8-16). Physiogonomy and structure of this bunchgrass-sagebrush savanna was presented in this slide that also showed spikes of bluebunch wheatgrass well-highlighted.
Unique feature of this rangeland location was that was included in two Level III Ecosystems: foreground was Columbia Plateau- Loess Islands Ecoregion,10b while background was Columbia Plateau- Channeled Scablands Ecoregion, 10a (Environmental Protection Agency, undated). Extreme background was the dramatically cut bank of Grand Coulee.
The short series of photographs that followed immediately below were of range vegetation in the valley of Grand Coulee (the background of this current photograph).
Coulee- "(a) A term applied in western U.S. to a small stream, often intermittent. Also, the bed of such a stream when dry. (b) A term applied in NW U.S. to a dry or intermittent stream valley, gulch, or wash of considerable extent; esp. a long, steep-walled, trench-like gorge or valley repreesenting an abandoned overflow channel that temporarily carried meltwater from an ice sheet, as the Grand Coulee (formerly occupied by the Columbia River) in Washington State (Gary et al., 1972).
The draw in the foreground of this photograph was a coulee as defined in (a) usage quoted above. Coulee as used in (b) was in the distant background and as presented in the next three photographs.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass).Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin.
44. Biggest channel yet- Three slightly different vantage point views featuring the range plant community in the valley floor of the biggest channel cut by the sequence of cataclymsic Bretz (Spokane) floods caused when ice (glacial) dams of Lake Missoula gave way . The bank of Grand Coulee served as "curtain" or backdrop landmark for another vegetational expression of the climatic climax Artemisia tridentata/Agropyron spicatum zonal association (Franklin and Dryness, 1973, ps. 211), the orignial Artemisia tridentata-Agropyron spicatum habitat type described by Daubenmire (1968,ps.iii, 8-16), which supported a much more botanically diverse plant community.
Herbaceous range plants present in addition to the two dominants included Sandberg's bluegrass, western or Nelson's needlegrass, needle-and-thread, and cheatgrass or downy brome, and Carey's balsamroot or rosy balsamroot (or a hybrid thereof), the most common forb. The major low shrub was rock or round-headed wild-buckwheat (Eriogonum sphaerocephalum) which was the associate shrub to basin big sagebrush. Together these two shrub species resulted in a two-shrub layer structure in this range plant community. Rabbitbrush species were"conspicuous by their absence" although undoubtedly there were a few isolated plants. Scattered dead plants of the Eurasian annual crucifer, tall tumble mustard, that had grown earlier in the spring were present, but these did not have the density or general abundance that was typical of abused shrub-steppe range.
The rangeland vegetation presented in these three slides was nearly contiguous with the basin big sagebrush-bluebunch wheatgrass range of the Loess Islands shown in the immediately preceding slide and several previous to that. Range plant communities on the predominately north slope, loess upland and on the valley floor of Grand Coulee were two different forms or variants of the Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968, ps.iii, 8-16). Obviously, these two forms (variants) of the same habitat type were two different--quite different--range sites. More on this later when yet other variant forms of this same habitat type were shown.
Range condition class of this range was Good with climax dominats being the most abundant and best-distributed range plants.
Grand Coulee is the ancient river bed of the Columbia River produced by a combination of 1) diversion of the river by glaciers and formation of Lake Columbia and 2) the series of cataclysmic Spokane floods caused when the glacier-dams of Lake Missoula gave way releasing ten to twenty times more water than in any river on Earth today, much of which followed the earlier glacier-carved river bed. Grand Coulee is the largest channel cut by the Spokane Floods, but erosion from these deepened and widened the previously glacier-formed channel. The spectacular bank of Grand Coulee as shown here is what remained after geologic erosion of deep layers of basalt laid down from erupting volcanoes in the Cascade Mountains several million years prior to the Ice Ages and their immense floods. The basalt depositions followed much earlier geologic phenomenon that produced an inland sea which over course of more recent geologic time was filled with igneous materials, especially basalt. This synopsis was drawn primarily from Allen et al. (1986), an excellent layman's-level reference that this author highly recommended to his readers.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass).Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin. Columbia Plateau- Channeled Scablands Ecoregion, 10a (Environmental Protection Agency, undated).
45. Rock or round-headed wild-buckwheat (Eriogonum sphaerocephalum)- Robust plant of round-headed wild-buckwheat growing on the basin big sagebrush-bluebunch wheatgrass shrub-steppe range in valley of Grand Coulee. Companion plant species to this hearty specimen were bluebunch wheatgrass, Sandberg's bluegrass, and cheatgrass.
Douglas County, Washington. June (early summer).
46. Flowering shoots and their flowers- Details of sexual shoots (including upper leaves of shoot) and flower cluster of rock or round-headed wild-buckwheat. Throughout the "Sagebrush Country" there are many Eriogonum species. Some of these are dominants and distinguish habitat types. Round-headed wild-buckwheat in the basin big sagebrush-bluebunch wheatgrass range that developed on the Grand Coulee valley presented above.
Douglas County, Washington. June (early summer).
47. A varied landscape (and its range vegetation)- In this part of the Okanogan Valley basin wildrye formed consociations in shallow potholes (swales or depressions) while big sagebrush-bunchgrass range communities developed on surrounding hills. On rangeland between these two vastly different range plant communities a relatively broad ecotone existed with large but scattered plants of basin wildrye and with interspaces among wildrye supporting a sward of inland saltgrass, bluebunch wheatgrass, Sandberg's bluegrass, needle-and-thread, western or Nelson's needlegrass, and (always) cheatgrass along with a few plants of big sagebrush. This transition zone was a classic Clementsian ecotone, but like the basin wildrye stands it was grassland not savannah. The big sagebrush-bluebunch wheatgrass (and associate grass species) shrub-steppe on hills was savanna.
Douglas County, Washington. June (early summer). Generally or overall this rangeland was FRES No. 29 (Sagebrush Shrubland Ecosytem) and K-49 (Sagebrush Steppe), but the within these there were three distinct climax range plant communities two of which were not covered by Society of Range Management rangeland cover types (Shiflet, 1994) or the Brown et al. (1998) biotic community classification system. SRM 314 (Big Sagebrush-Bluebunch Wheatgrass).Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau not Great Basin. The basin wildrye-inland saltgrass-bunchgrass ecotone was the Elymus cinereus-Distichlis spicata habitat type (Daubenmire, 1968, ps. iii, 50-51), but the single-species stands of basin wildrye (except for a few cheatgrass plants) did not have a habitat type. The Brown et al. classification system (1998) should have a Basin Wildrye Series under a Columbia Plateau Shrub-Grassland. Columbia Plateau- Okanogan Valley Ecoregion, 10m (Environmental Protection Agency, undated).
48. Two different kinds of range (or what difference water makes)- Closer-in view of the basin wildrye consociation and the ecotone between basin wildrye and big sagebrush-bluebunch wheatgrass savanna (shrub-steppe). The latter was the range vegetation on the hills in background (which was featured immediately below) The transistion zone was a grassland of mixed bunchgrass and inland saltgrass.
Scale or relative size of basin wildrye was shown by the steel, studded T fencepost in left foreground.
Douglas County, Washington. June (early summer). Generally or overall this rangeland was FRES No. 29 (Sagebrush Shrubland Ecosytem) and K-49 (Sagebrush Steppe), but neither of these range plant communities was covered by either the Society of Range Management rangeland cover types (Shiflet, 1994) or the Brown et al. (1998) biotic community classification system. It was remarked periodically in this publication that there should have been an SRM Basin Wildrye rangeland cover type under Pacific Northwest, Northern Rocky Mountains, and/or Great Basin Cover Types (Shiflet,1994). The Brown et al. classification system (1998) should have a Basin Wildrye Series under a Columbia Plateau Shrub-Grassland. Columbia Plateau- Okanogan Valley Ecoregion, 10m (Environmental Protection Agency, undated).
49. Variation on the same theme- Another expression of the big sagebrush-bluebunch wheatgrass shrub-steppe, and another form or variant of the Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Vegetation on this range had western or Nelson's needlegrass as the associate grass species to bluebunch wheatgrass. Sandberg's bluegrass, needle-and-thread, and, of course, cheatgrass were present, but on big sagebrush-bluebunch wheatgrass rangeland like that which Daubenmire (1968, Fig. 2,p. 10) showed as the "Artemisia tridentata-Agropyron spicatum association in pristine condition" western needlegrass was clearly the second most abundant grass. This range vegetation that developed on hills in the Okanogan Valley was similar to that in the Loess Islands Ecoregion that was described in detail, but there was certainly more western or Nelson's needlegrass while balsamroot species were absent on the big sagebrush-bluebunch wheatgrass steppe featured here. Impacts (if any) of grazing history were unknown.
Physiogonomy and structure of this big sagebrush-bunchgrass range was presented in this photograph.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass).Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau (not Great Basin) Shrub-Grassland. Columbia Plateau- Okanogan Valley Ecoregion, 10m (Environmental Protection Agency, undated).
50. Interior of the big sagebrush-bluebunch wheatgrass (western or Nelson's needlegrass)- Species composition view of another form or variant of the climatic climax Artemisia tridentata-Agroypon spicatum zonal association that is widespread over the Columbia Plateau. The major (though it was uncommon) forb was western yarrow (Achillea millefolium var. lanulosa). Nelson's or western needlegrass was well-represented, but not conspicuous in this photograph..
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass).Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau (not Great Basin) Shrub-Grassland. Columbia Plateau- Okanogan Valley Ecoregion, 10m (Environmental Protection Agency, undated).
51. Still more variation on the same theme- Another variant of different form or phase of the climatic climax Artemisia tridentata-Agroypon spicatum zonal association and the corresponding Artemisia tridentata-Agroypon spicatum habitat type (Daubenmire, 1968, ps.iii, 8-16; Franklin and Dryness, 1973, ps. 211, 216-218) with a more species-diverse range plant community and another soil than of those presented above.
Wide-scale perspective of a sandy land variant of the big sagebrush-bluebunch wheatgrass shrub-steppe with a remarkable diversity of range plants including in addition to the co-dominants Sandberg's bluegrass, Cussick's bluegrass (Poa cusickii), needle-and-thread, cheatgrass, thread-leafed sedge (Carex filifolia), and western yarrow as major herbaceous species with narrowleaf fleabane (Erigeron linearis) as first runner-up range forb, and rubber rabbitbrush (Chrysothamnus nauseosus), little-leaf horsebrush (Tetradymia glabrata), and three-tip or cut-leafed sagebrush (Artemisia tripartita).
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass).Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968, ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau (not Great Basin) Shrub-Grassland. Columbia Plateau- Okanogan Valley Ecoregion, 10m (Environmental Protection Agency, undated).
52. Zooming in on more variation- Two photo-plots of the sandy land form of the big sagebrush-bluebunch wheatgrass shrub-steppe range introduced in the preceding photograph. Important and common grasses included bluebunch wheatgrass, Sandberg's bluegrass, Cusick's bluegrass, needle-and-thread, and, of course, the Eurasian invader, cheatgrass. There was (were) no obvious associate shrub species to basin big sagebrush though rubber rabbitbrush, little-leaf horsebrush, and three-tip or cut-leafed sagebrush were all important at local scale. The main forb was western yarrow. Cover of cheatgrass was limited; this range was probably in Good range condition class.
Douglas County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosytem). K-49 (Sagebrush Steppe). SRM 314 (Big Sagebrush-Bluebunch Wheatgrass).Artemisia tridentata-Agropyron spicatum habitat type (Daubenmire, 1968,ps.iii, 8-16). Wheatgrass-Shrub Series of Brown et al. (1998), but should be Columbia Plateau (not Great Basin) Shrub-Grassland. Columbia Plateau- Okanogan Valley Ecoregion, 10m (Environmental Protection Agency, undated).
Range site versus habitat type: It was discussed in the Literature Review herein (Range Site- Range Site vs. Habitat Type) that range site and habitat type are two related, even similar, concepts and units of native vegetation and land (primarily soil), but that they are different and distinct from one another (ie. thay are not synonymous). Some of the more recent interpretations and definitions of habitat type and range (= ecological) site by some organizations or individuals have stressed the similarity of these two units of classification. The fourth edition of the Society for Range Management Glossary of Terms Used in Range Management (Bedell, 1998) specified that difference between these two units depended "mainly on how specifically plant associations are defined".
Indeed. As Daubenmire (1968,ps.iii, 8-16) was cited repeated above, Artemisia tridentata-Agropyron spicatum habitat type and Artemisia tridentata-Agroypon spicatum zonal association were apparently synonmous such that this (these) unit(s) of classification covered many different forms, variants (or whatever the appropriate term would be) of shrub-steppe range vegetation that was dominated by these two species. Four distinctive kinds of rangeland in the Columbia Basin that were dominated by big sagebrush and bluebunch wheatgrass (= four different kinds of shrub-steppe with four different soil series or associations) were shown and described generally above. These four different ranges (land management units) were representative of four different kinds of rangeland. The four different kinds of big sagebrush-bluebunch wheatgrass shrub-steppe rangeland were obviousy four distinct range sites, but they were all one habitat type.
The four kinds of big sagebrush-bluebunch wheatgrass shrub-steppe presented above served as examples of the fact that habitat type and range site are not synonymous. They are two similar and different units of classification. At least such was the case for these examples. Some of the habitat types of steppe and shrub-steppe defined by Daubenmire (1968) were edaphic climaxes whereas others were climatic climaxes that were of greater spatial scale and more general distribution. The latter are regarded as zonal associations. Some of these habitat types that are zonal associations are closer to range types (ie. dominance types, including most rangeland and forest cover types) whereas the edaphic climaxes are more similar to or consistent with range sites. This would seem to be the situation whenever the habitat type is based on vegetation, specifically the dominant plant species of the major layers of vegetation, rather than being based on edaphic or other physical feature (oil series or association, relief, etc.) as is the case for range sites. Range sites are the smallest, most distinctive unit of classification whereas zonal associations are some of the largest spatial-scale units that would by definition and inclusiveness include several smaller classification units.
In effect, habitat types define vegetation and seek to make plant communities fit the land that was described after the vegetation was chosen. Range sites by contrast define the land (soils, topographic features) and then describe plant communities that fit land characteristics. There were bound to be some inconsistencies and lack of fit between these two classification units.
53. Threadleaf or thread-leafed sedge (Carex filifolia)- This species has generally been regarded as the--at least one of the--most important forage carices in North America. Unlike many sedges threadleaf sedge is a not a wetland species, but is instead a range plant of semiarid regions that includes some kinds of mixed prairie, bunchgrass prairie, shrub-steppe, and even understories of some open canopy forests. The specimen presented here and in the two subsequent photographs was growing on the range last described above that was typical of the sandy land form of big sagebrush-bluebunch wheatgrass shrub-steppe range that was in Good range condition class.
Threadleaf sedge was treated by numerous workers in standard range plant references and texts including Forest Service (1940, GL5), Weaver and Albertson (1956, ps. 39-4,216), Hermann (1970, ps. 202-203), and Hurd et al (1998, ps.112-113). Threadleaf sedge was one of two carices selected for inclusion in the Society for Range Management International Intercollegiate Range Plants Contest. As such C. filifolia was included in North American Range Plants of which this author preferred the fourth edition (Stubbendieck et al., 1992, ps. 326-327).
Douglas County, Washington. June (early summer).
54. Taking a closer look at thread-leaf sedge- Details of shoots and inflorecences of thread-leafed sedge at dormancy and with very dry material. The inflorescences were at immediate pre fruit-shatter stage (most had already shed).
Forage value of threadleaf sedge has traditionally been regarded as good to excellent (see for eg. Hermann, ;1970, p. 202). This is one of the most valuable grasslike plants on the Western Range for livestock and wildlife forage. It is also extremely valuable for soil protection, especially wind erosion.
Douglas County, Washington. June (early summer). Dormancy, right at fruit-shatter stage.
55. Littleleaf horsebrush (Tetradymia glabrata)- Individual of littleleaf horsebrush growing on the sandy land, big sagebrush-bluebunch wheatgrass shrub-steppe range presented in the three-slide set used above.
Douglas County, Washington. June (early summer).
56. Shoots and flowers of littleleaf horsebrush- Details of shoots and inflorescences of littleleaf horsebrush growing on the sandy land big sagebrush-bluebunch wheatgrass range shown in the three photographs presented earlier.
Douglas County, Washington. June (early summer).
57. Three-tip sagebrush (Artemisia tripartita)- Small specimens of threetip sagebrush in early stages of sexual shoot formation. As sexually reproductive shoots of this Artemisia species develop (grow to maturity) they form several units of flower clusters along their length. In examples shown here the first of such clusters were forming at apices of shoots. Shoots had not begun to elongate.
There is considerable variation is shape of leaves among individuals of threetip sagebrush. Some leaves have comparatively broader width, deeper lobes, or overall greater size than others, including those on the same plant. Species as disparate in size as threetip sagebrush and basin big sagebrush obviously occupy ecological niches that differ greatly from each other. On big sagebrush-dominated shrub-steppe the physical space of the threetip sagebrush ecological niche is much smaller, and perhaps, available only in localized microhabitats.
However confined their niche, these cute little fellows added biodiversity and beauty to this relatively species-diverse range.
Douglas County, Washington. June (early summer). Early pre-bloom, pre-shootelongation stage.
58. Narrowleaf fleabane (Erigeron linearis)-This member of the aster tribe was also making its home on the big sagebrush-bluebunch wheatgrass shrub-steppe range in Okanogan Valley of the Columbia Plateau described here. Another species of yellow composite. June; full-bloom..
59. Big sagebrush-needle-and-thread shrub-steppe- Two slightly different vantage points of another edaphic climax association of shrub-steppe rangeland vegetation. Franklin and Dryness (1973, ps. 224-225) listed and briefly described four Stipa comata associations of deep soils. Two of these were the Artemisia tridentata/Stip comata and the Purshia tridentata/Stipa comata associations. The "$64,000 question" was, which of these two associations was presented in these two photographs? Your call observant viewer. The author used these slides to provide some indiction as to the species composition, structure, and physiogonomy of both of of these Stipa comata associations. Range vegetation in these photographs can be be compared to that in figures 14 and 15 of Daubenmire (1968,ps. 34 and 35, respectively). Obviously browsing by almost any species would be more likely to shift shrub dominance to the less palatable big sagebrush. Browsing use of this range was unknown, but there were tracks and dung of mule deer present.
Other species present obviously included cheatgrass, bluebunch wheatgrass, and less Sandberg'sbluegrass. Surprising (perhaps) given the deep sand of this range site there was respectable cover of Idaho fescue. Rubber rabbitbrush was also present. The most common forb appeared to be slender hawksbeard (Crepis atribarba).
The two Stipa comata associations of Franklin and Dryness (1973, ps. 224-225) corresponded to the earlier published Artemisia tridentata-Stipa comata habitat type and Purshia tridentata-Stipa comata habitat type of Daubenmire (1968, ps. iii, 34-36) which provided yet another example that the habitat type as developed by Rexford Daubenmire corresponds--at least with many kinds of range vegetation--to the association which, obviously, is a larger, more general classification unit than the range site (there would be several range sites within each association).
Botanical and general ecological affinity between this mixed shrub/needle-and-thread shrub-steppe was explained in the following from Franklin and Dryness (1973, p. 224): "The Artemisia tridentata/Stipa comata association is very similar to the Artemisia tridtata/Agrppyron spicatum physiognomically and floristically except for the substitution of Stipa for Agropyron".
Mighty fine shrub-steppe range however one views ("browses") it.
Chelan County, Washington. June (early summer). FRES No. 29 (Sagebrush Shrubland Ecosystem). K-50(Wheatgrass-Needlegrass Shrubsteppe). No SRM rangeland cover type (should be an Antelope Bitterbrush-Needle-and-Thread under Pacific Northwest Cover Types and/or Northern Rocky Mountains and a Big Sagebrush-Needle-and-Thread under one of both of these areas; literature clearly showed existence of such an association or rangeland cover type). Either Artemisia tridentata-Stipa comata habitat type or Purshia tridentata-Stipa comata habitat type (Daubenmire, 1968, ps. iii, 34-36). If Brown et al. (1998) had a Columbia Plateau Shrub-Grassland (as they did for Great Basin Shrub-Grassland) this would be Needle-and-thread Series thereunder. North Cascades- Chiwaukum Hills and Lowlands Ecoregion, 77h (Environmental Protection Agency, undated).
60. Needle-and-thread (Stipa comata) on Columbia Plateau range- Needle-and-thread is one of the important dominant species on some range types and range sites in the shrub-steppe range region. The two immediately preceding photographs presented one of the more important Stipa comata associations (and habitat types) of the region. Needle-and-thread is a widespread dominant of both the mixed prairie and the bunchgrass prairie as well as in the shrub-steppe. Needle-and-thread was one of three species whose dominance or general abundance across vast reaches of both the bunchgrass prairie and the mixed prairie and then into contacts with the sagebrush-steppe that convinced Clements (1920, ps. 149-150, 155) of the affilitation of these three major units of range vegetation.
Clements (1920, p. 151) regarded as needle-and-thread as the most mesophytic of the Stipa species in the bunchgrass prairie which included the Stipa species of the pre-Columbian California prairie. The mesophyic nature of needle-and-thread largely explained its preference for deeper soils such as sand (Franklin and Dryness, 1973, ps. 224-225) as seen in the example prresented here.
Chelan County, Washington. June (early summer).
61. Business end of needle-and-thread- Some spikelets of needle-and-thread with ripe grain separated from glumes.The sharp (acutely pointed) and hard callus of this species can cause serious mechanical injury, especially in sheep. This is one of the most appropriate common names of any species of North American grass.
Chelan County, Washington. June (early summer).
62. Slender hawksbeard (Crepis atribarba)- One of the more common forbs on the shrub (either big sagebrush or antelope bitterbrush)- needle-and-thread range featured above. Crepis species are in the Cichorieae (chicory tribe) of the Liguliflorae subfamily of the Compositae.
Chelan County, Washington. June (early summer). Full-bloom stage of phenology.
A difficult and, at best, arbitrary one to classify- In the Townsend Basin and foothills just above of western Montana range vegetation with bluebunch wheatgrass and Wyoming big sagebrush takes on "various forms" plus this grassland that "blends into" to shrub-grass savanna "joins up with" ponderosa pine to form a bunchgrass-shrub-tree savanna and then becomes a ponderosa pine-bunchgrass woodland.
At either extreme of this continuum (grassland and woodland) range vegetation clearly belongs to bluebunch wheatgrass-dominated grassland or to ponderosa pine-bludbunch wheatgrass woodland (or even forest). In between there are climax range plant communities that could fit either Palouse Prairie bunchgrass steppe or Wyoming big sagebrush-bluebunch wheatgrass shrub steppe.
In order to be as inclusive as possible and to aid students some of these climax range types (or subtypes) have been included in both the current chapter as well as in the other Grassland chapter entitled Palouse Prairie.
The ponderosa pine-bluebunch wheatgrass savanna to woodland that had developed in the foothills (sedimentary hills) just above the Townsend Basin was included in the Forest & Grassland chatper entitled Southern & Middle Rocky Mountain Forests.
63. A large relict- Large expanse of a cattle (also any wildlife such as deer and pronhorn) range that was a drier range site in the Townsend Basin on which a consociation of bluebunch wheatgrass had developed. Green needlegrass (Stipa viridula) and Idaho fescue were also present though hardly at proportions (cover, density, etc) to qualify as associate grass species. Wyoming big sagebrush (Artemisia tridentata subsp. wyomingensis) and plains pricklypear (Opuntia polycantha) added a shrub component which was present as two interrupted or sporadic shrub layers. This livestock and big game range served as an ideal or perfect example of the bunchgrass grassland of the Palouse Prairie. Range vegetation presented here and in slides immediately below was a tract of relict or virgin range vegetation even though it was being grazed by large ruminants (native and domesticated). Superb example of wise use management; outstanding range conservtion. An example of perfect stewartship of the natural grazing resources.
This relict area served as a range reference area, a range that was--from we can tell after the fact--representative of the pre-Columbian range vegetation on this part of the Northern Great Plains. Although the botanical composition or plant species diversity was low in this range plant community it was the climax vegetation and in Excellent range condition class. Species diversity along with community composition and structure are often low and more homogeneous than hetrogeneous in climax range vegetation. Students must understand the concept of the climax consociation in which one plant species is the clear dominant and, not infrequently, almost the sole species. For example Clements (1920, p. 150) specified that bluebunch wheaqtgrass "...is the major and often the exclusive dominant throughout the Palouse [Prairie], southward into Oregon and California and eastward into Idaho and Montana".
The first of these three slides was a scanned image that accurately reproduced features (colors, clarity, etc.) of plants, soil, and sky whereas the second and third slides were botched successively worse by an Epson Perfection 700 scanner. The third slide was nearly worthless, but it did covey the idea (though certainly the image) of general size and green color of a population of bluebunch wheatgrass. The third slide (which was a nearly perfect image with good depth of field before Epson Perfection "perfected" it) also included several plants of plains pricklypear in the foreground and a large plant of Wyoming big sagebrush in midground.
Although this bit of Palouse Prairie was in the Northern Rocky Mountain physiographic province (Fenneman, 1931, ps. 184, 214-215) and not the Northern Great Plains it was still part of the Palouse Prairie. Natural vegetation and physiographic provinces are not exact fits just as range vegetation and climate do not coincide or correlate perfectly. This part of the Northern Great Plains and Northern Rocky Mountains adjoin and form enclaves with each other (see Figure 82, p. 220 of Fenneman, 1931).
Townsend Basin or Valley, Lewis & Clark County, Montana. Late June; estival aspect. FRES No. 38 (Plains Grassland Ecosystem). K-59 (Wheatgrass-Needlegrass). SRM 101 (Bluebunch Wheatgrass) as applied to the Northern Rocky Mountain Cover Types. In Brown et al. (1998, p. 40) it would (there should) be Wheatgrass Series 142.1(say, 4) of Plains Grassland 142.1 of Cold Temperate Grassland 142 of Grassland Formation 140. Foothills & Mountains- Limy-Shallow-Very Shallow range site complex- 10-14 inch precipitation zone. (Ross and Hunter, 1976, ps. 27-28). Middle Rockies- Townsend Basin Ecoregion 17w (Woods et al., 2002).
64. Outward and structural appearances- Physiography, structure and overall composition of a bluebunch wheatgrass consociation of the Palouse Prairie in Excellent range condition class. Green needlegrass and Idaho fescue were secondary grass species hardly worthy of being designated as associates, but these three decreaser grasses comprised almost all of the herbaceous biomass. Cheatgrass (Bromus tectorum) was the same as non-existent on this range. This range vegetation was "el primo".
The first of these two slides showed plants of Wyoming big sagebrush, which was the major shrub (of two species for all practical purposes), and moderate degree of use around the sagebrush on this cattle range. The second slide provided an ungrazed "photoplot" (part of the range that had received very little use by cattle or wildlife) for comparison. This second slide illustrated the large-sized and rank-growing habit of which the midgrass bluebunch wheatgrass is capable. Green needlegrass, some of which were present in this view of the sward, can grow to similar size and dimensions. Idaho fescue is typically shorter in stature and generally of smaller size.
This range plant community had developed in the Northern Great Plains adjoining the Northern Rocky Mountains. Grasslands and forests develop in close proximity in this part of the Interior Northwest.
Townsend Basin or Valley, Lewis & Clark County, Montana. Late June; estival aspect. FRES No. 38 (Plains Grassland Ecosystem). K-59 (Wheatgrass-Needlegrass). SRM 101 (Bluebunch Wheatgrass) as applied to the Northern Rocky Mountain Cover Types. In Brown et al. (1998, p. 40) it would (there should) be Wheatgrass Series 142.1(say, 4) of Plains Grassland 142.1 of Cold Temperate Grassland 142 of Grassland Formation 140. Foothills & Mountains- Limy-Shallow-Very Shallow range site complex- 10-14 inch precipitation zone. (Ross and Hunter, 1976, ps. 27-28). Middle Rockies- Townsend Basin Ecoregion 17w (Woods et al., 2002).
65. Internal appearances- Interior of a bluebunch wheatgrass-dominated Palouse Prairie cattle range in the Townsend Basin or Valley. The first of these two slides presented degree of use (and cattle dung showing that cattle had grazed this range) of bluebunch wheatgrass by including both representative degree of use and ungrazed bluebunch wheatgrass plants. The second slide featured mostly ungrazed plants of bluebunch wheatgrass. There was considerable range in size, both diameter of these cespitose plants as well as in height of their tillers. It was possible that larger plants were older while individuals of samller size were younger (perhaps the progeny of the larger individuals).
It was even more likely that larger plants were wolf plants that had not been grazed for as many as several consecutive years. Wolf plants in this context are those individual plants that, though of a species that is generally palatable, are not grazed by range animals (Kothman, 1974). Kothman (1074) also defined wolf plants as isolated plants that have grown to unusually large size often due to lack of or limited competition. This second meaning was less likely, but on bunchgrass prairie individual cespitose plants are often of such wide spacing that there might, in fact, be very little competition (as for water or soil nutrients for instance).
Townsend Basin or Valley, Lewis & Clark County, Montana. Late June; estival aspect. FRES No. 38 (Plains Grassland Ecosystem). K-59 (Wheatgrass-Needlegrass). SRM 101 (Bluebunch Wheatgrass) as applied to the Northern Rocky Mountain Cover Types. In Brown et al. (1998, p. 40) it would (there should) be Wheatgrass Series 142.1(say, 4) of Plains Grassland 142.1 of Cold Temperate Grassland 142 of Grassland Formation 140. Foothills & Mountains- Limy-Shallow-Very Shallow range site complex- 10-14 inch precipitation zone. (Ross and Hunter, 1976, ps. 27-28). Middle Rockies- Townsend Basin Ecoregion 17w (Woods et al., 2002).
66. Internal structure- Structure and species composition of a cattle and big game range on the Palouse Prairie that was a consociation of bluebunch wheatgrass. This range plant community was almost a single-species stand of this decreaser dominant of the Interior Pacific, cool-season, bunchgrass range type. The first (horizontal) slide was a slanted downward view through this bunchgrass prairie to shown the dispersion pattern and habit of range plants. The second (vertical) slide was a top-down view showing structure, including widely-spaced dispersion, of the climax vegetation of this range, a range that was in Excellent range condition class. The second photograph also showed plants of plains pricklypear and those of the smaller Idaho fescue.
The high proportion or percentage of bare ground seen in these two slides was typical of that on northwest bunchgrass prairie. It is the nature of certain consociations, especially those with cespitose species and that are in essentially virgin or pristine condition, to have considerable area of bare soil surface and low numbers of plant species (low biodiversity; a simple species composition).
This range plant community was on the Northern Great Plains in close proximity to the Northern Rocky Mountains (Fenneman, 1931, ps. 184, 220). Such natural vegetation is equally "at home" on the plains and in the foothills of the Northern Rockies.
Townsend Basin or Valley, Lewis & Clark County, Montana. Late June; estival aspect. FRES No. 38 (Plains Grassland Ecosystem). K-59 (Wheatgrass-Needlegrass). SRM 101 (Bluebunch Wheatgrass) as applied to the Northern Rocky Mountain Cover Types. In Brown et al. (1998, p. 40) it would (there should) be Wheatgrass Series 142.1(say, 4) of Plains Grassland 142.1 of Cold Temperate Grassland 142 of Grassland Formation 140. Foothills & Mountains- Limy-Shallow-Very Shallow range site complex- 10-14 inch precipitation zone. (Ross and Hunter, 1976, ps. 27-28). Middle Rockies- Townsend Basin Ecoregion 17w (Woods et al., 2002).
Back to some Wyoming big sagebrush-bunchgrass range vegetation that was "easier to place" and less arbitrary as to its vegetation classification "pigeon hole".
67. Powder River savanna- Big sagebrush-mixed grass prairie savanna in Powder River Basin. This was a savanna of Wyoming big sagebrush (Artemisia tridentata subspecies wyomingensis) with the co-dominant climax decreaser grasses being Canby bluegrass (Poa canbyii) and western wheatgrass (Agropyron smithii). Other important grass species included green needlegrass (Stipa viridula), Junegrass (Koleria cristata), and blue grama (Bouteloua gracilis). Only the latter species (an eragrostoid grass) was a warm-season species, all others were cool-season festucoid species. There was same as no cheatgrass or downy brome (Bromus tectorum), a widespread, naturalized, Eurasian annual grass, on this pristine shrub-grass savanna that was in Excellent range condition class. The other shrub species growing on this range was plains pricklypear (Opuntia polycantha).
These two slides presented physiogonomy and overall structure of this range plant community. There were large areas of this range that had no shrub component. Such areas were grassland--a bluegrass variant of SRM 608 (Wheatgrass-Grama-Needlegrass)--and not savanna. An exampe of this bluegrass variant of wheatgrass-grama-needlegrass grassland existing on this same range was presented in the immediately succeeding slide.
Bittersweet (Lewisia rediviva) and common pepperweed (Lepidium densiflorum) were the only two forb species found in the photographed range vegetation. Bittersweet was so low-growing that it could be seen as comprising a second (a lower) herbaceous layer. Bittersweet had such a widely spaced presence (cover) on this savanna range that it would clearly be or represent a very eradic or sporadic "layer".
In the vernal society of this range plant community There were only two distinct layers of this range vegetation: 1) shrub layer of Wyoming big sagebrush and 2) herbaceous layer of mid-grass species. Later in the year there would be something of a third layer, a shortgrass layer, due to cover of blue grama. It was likely that blue grama, would attain heights similar to those of the cool-season grasses so that presence of a second herbaceous layer was somewhat questionable or arbitrary.
In local areas there was a popultion of the fungal-algal organism, tumbleweed shield lichen ((Xanthoparmelia chlorochroa= Parmelia chlorochroa) that represented a sporadic ground layer of this range vegetation. This was the case if a rangeman regarded this sometimes toxic, non-vascular pteriophyte as a range plant, as your author most certainly did. Plains pricklypear--though limited in cover--presented another problem in describing the structure of this range vegetation because this low-growing cactus could be regarded as making up a second woody or shrub layer in this range community. The lower layer(s) of this range vegetation was presented below.
This range vegetation was in a state of mild drought that probably hastened grass maturity (completion of annual life cycle). No livestock grazing had occurred on this range during year of photographs.
Johnson County, Wyoming. Mid-June; late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem). K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004).
68. No shrubs here- A large area grassland within an overall Wyoming big sagebrush-mixed grass prairie savanna in Powder River Basin. The only difference between range vegetation seen here and that in the two immediately preceding slides was absence of Wyoming big sagebrush. Both forms of range vegetation were on the same livestock range within a few hundred yards of one another. (There had not been livestock use of this range during the current growing season, the year when these photographs were taken.)
C o-dominant species in this range plant community western wheatgrass and Canby bluegrass. Other important--basically local associate--species were green needlegrass, Junegrass, and blue grama. This latter was the only warm-season grass found on the photographed portion of this range.
Johnson County, Wyoming. Mid-June; late vernal aspect. FRES No. 38 (Plains Grssaland Ecosystem). K-59 (Wheatgrass-Needlegrass). SRM 608 (Wheatgrass-Grama-Needlegrass), bluegrass variant. Closest biotic community in Brown et al. (1989, p. 40) was still the Mixed Grass-Shrub Series 142.22 of Great BasinShrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004).
69. A difference in the lay of the land- A shallow draw supported a local consociation of western wheatgrass whereas a savanna of Wyoming big sagebrush, western wheatgrass, Canby's bluegrass, green needlegrass, Junegrass, and blue grama had developed on the drier slopes surrounding the draw. This range vegetation developed in the Powder River Basin in central Wyoming.
The first slide presented an oblique view of these two distinct local range plant communities whereas the second slide presented a view straight up the draw which served as a "photographic transect". There was a distinct boundry between sod of the rhizomatous western wheatgrass and the shrub-grass savanna. This was particularly noticable in the second, vertical slide. Note in this vertical slide that a few small plants of Wyoming big sagebrush had established in the sward of western wheatgrass. Would the savanna form eventually develop even in the more mesic (less xeric) environment of the draw?
Johnson County, Wyoming. Mid-June; late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem). K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004).
70. Phyto players up close- A "photoquadrant" of the herbaceous layer (or layers) of a Wyoming big sagebrush-mixed grass savanna that developed in the Powder River Basin of central Wyoming. The herbage seen in this slide was primarily Canby bluegrass (foreground) and western wheatgrass (background). A bright pink bitterroot adorned left foreground.
Johnson County, Wyoming. Mid-June; late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem). K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004).
71. Looking down through sward- Two topdown views of the open sward of the herbaceous layer of a Wyoming big sagebrush-mixed grass savanna in the Powder River Basin of central Wyoming. This sward was do-cominated by Canby bluegrass and western wheatgrass. Other native grass species included green needlegrass, Junegrass, and blue grama. Blue grama was the only major species that was a warm-season (an eragrostoid) grass. At this season of late spring (and in a mild drought) blue grama, typically a shortgrass species, was in early growth stages and was not a major component of the vernal society of this climax range vegetation. Blue grama would be a much more important component--from perspective of cover and biomass--in the estival society of this climax plant community. Still, blue grama was a seasonal associate species in range vegetation dominated by festucoid (cool-season) grasses.
No plants of Wyoming big sagebrush were present in these "two photoplots", the first or upper of which covered a larger area of ground surface. The smaller-sized "photoplot" included primarily tufts of Canby bluegrass with areas of largely bare soil except for cover of tumbleweed shield lichen, a potentially toxic organism to grazing animals. Although tumbleweed shield lichen, a mutualistic union of fungus and algae, is not a vascular plant it can be considered to be part of the range vegetation of this shrub-mixed grass savanna. Older generations of rangemen, including the "baby boom" generation of college graduates (of which your author is a member), were taught and passed on the teaching that lichens were plants, nonvascular spore-producing plants known generically as thallophytes. (Examples and discussion of tumbleweed shield lichen were presented below in this section.)
Johnson County, Wyoming. Mid-June; late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem). K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004).
Historical note: one of the most notorious, bitterest, hard-fought range wars in history of the Western Range was the so-called Johnson County Powder River War, or Wyoming Range War. The classic narrative of this bloody conflict that brought in the US Army was that of (Smith, 1966). The proverbial "great read".
72. When management of the range resource is improper: A grazing (and, perhaps, fire suppression) disturbance climax of a former climax Wyoming big sagebrush-mixed grass savanna in the Powder River Basin of central (to northcentral) Wyoming. This disclimax range was a shrubland dominated by Wyoming big sagebrush with two different herbaceous underestoreies that had developed in two zones or "strips" under the shrub layer. One, the narrower, of these "strips" had developed on the perimeter of this deteriorated range along an interstate highway. This narrow perimeter "strip" consisted of the introduced Eurasian pereennial grasses, smooth brome (Bromus inermis) and crested wheatgrass (Agropyron cristata) with some cover of the native perennial, Sandberg's bluegrass. The wider, interior "strip" of herbaceous understorey was comprised almost exclusively of the Eurasian annual grass, cheatgrass or dowy brome. The narrower, perimeter "strip" or zone of perennial grass understorey (herbaceous layer) was shown in the foreground of both photographs above.
There were two prominent forbs in the understorey of this disclimax shrubland. Both of these were exotic and, now, widely naturalized Eurasian perennials: field bindweed (Convolvulus arvensis) and common dandelion (Taraxacum officinale). These two forbs grew throughout the understorey, but they had greater cover in the perimeter zone of perennial grasses; the denser, more nearly complete cover of cheatgrass produced more shade and, by some mechanisms, appeared to offer greater competition to the broad-leafed, perennial weeds.
This deteriorated Wyoming big sagebrush-mixed grass savanna or a form of shrub steppe had become a brush-infested "cow pasture" or a "brush field", a single-species stand of brush (noxious woody plants; weedy woody species) with a sporadic understorey of introduced pasture grasses and alien weeds. This range was currently being grazed by cow-calf pairs, but it likely had been grazed over the course of domestic animal use by various kinds and classes of livestock ranging from sheep to horses and probably stocker cattle as well as pairs. It was most probable that range deterioration (retrogression of range vegetation) had taken place decades earlier, likely during the open range era (this general area was the location of some of the bloodiest range wars in United States history). Based on current overuse of smooth brome and heavy grazing of crested wheatgrass it was obvious that current grazing was still improper (eg. perhaps excessive stocking rates, incorrect season of use, inadequate distribution of cattle).
Not exactly a delightful, placid pastoral picture; but in combination with the preceding section of a Wyoming big sagebrush-mixed grass savanna (that was in high Good to Excellent range condition class) this sad scene taught a textbook lesson to students of Range Management. These two pastures were in different (though similar) range sites, but in the same range cover type and climate.
Sheridan County, Wyoming. Mid-June. This range plant community was a degraded representative of the following vegetational units. FRES No. 29 (Sagebrush Shrub Ecosystem). K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Biotic community in Brown et al. (1989, p. 40) was Shrub-Grass Disclimax Association 142.131 of Plains Grassland 142.1, Cold Temperate Grassland 142. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004).
73. Living footprint of Meriweather Lewis- Two plants of bitterroot (Lewisia rediviva) at immediate pre-bloom (left) and early bloom (right) stages on a Savanna of Wyoming big sgebrush and , another example of the immense sagebrush shrub steppe acrosss the Western Range Region.
Johnson County, Wyoming. Mid-June; early bloom stage.
74. You'd have to be blind to miss this one- Two specimens of bitterroot each with about one-third of its flowers opened. Bitterroot is in the portulaca family. Portulaceae does not have many members, but a large propotion of these have showy flowers or uniques habits. The portulaca family more than made up for small numbers with flowers like this. Bitterroot is the State Flower of Montana.
Johnson County, Wyoming. Mid-June; mid-bloom stage.
75. "Jist don't come any purtier"- One opened and one unopened flower of bitterroot on a Wyoming big sagebrush-mixed prairie savanna.
Johnson County, Wyoming. Mid-June; mid-bloom stage.
76. Nice example- Wolf lichen (Letharia vulpina) on dying lower shoot (trunk) of Wyoming big sagebrush. Lewis & Clark County, Montana. Late June.
77. A poisonous symbiosis- Tumbleweed shield lichen ((Xanthoparmelia chlorochroa= Parmelia chlorochroa) on a Wyoming big sagebrush-needle-and-thred--threadleaf sedge--Sandberg bluegrass shrub steppe in the Wyoming Basin. This lichen is in family Parmeliaaceae, Lecanorales order.
First (upper) slide was in Johnson County, Wyoming; second (lower) slide was in Fremont County, Wyoming. Mid-June and late June, respectively.
78. The utimate expression- Two views of the climax range vegetation of a Wyoming big sagebrush-mixed bunchgrass savanna or shrub steppe in the Northern Great Plains. Specifically, this range landform consisted of a series of ridges and shallow ravines on the uplands above the Valley of the Little Bighorn River. This is one of the more easterly, more mesic (clayey to shallow clayey soils) environments on which the Wyoming big sagebrush-mixed grass steppe develops. In this regard, the climax range vegetation presented here is an example of some of the greatest degree of expression of this range type.
The dominant plants in the example of this rangeland cover type varied from areas on which tri-dominants bluebunch wheatgrass, green needlegrass, and needle-and-thread were tri-dominants to the general or overall situation in which bluebunch wheatgrass was the dominant and needle-and-thread and green needlegrass were associate species. Dominant plant species were therefore climax (decreaser), cool-season, festucoid grasses. In local areas associate (and, also, decreaser) species were sideoats grama (Bouteloua curtipendula) and blue grama (B. gracilis). These latter native grasses were warm-season, eragrostoid species. All of these grass species usually grow as bunchgrasses (cespitose or tufted grass species) and all except blue grama are usually described as mid-grass species. This range plant community is a textbook example of the big sagebrush-bunchgrass steppe, a savanna form of mixed prairie or, perhaps, even true prairie.
Forbs were limited in cover and species and, in this vernal society, limited to Nuttall's mariposa or sego lily (Coalchortus nuttalli), a native perennial arising from a large bulb.
Plains pricklypear (Opuntia polycantha) was a second woody plant species in thie range plant community so that there were two interrupted woody layers in this climax shrub-steppe vegetation.
A wild prairie fire in 1983 (30 years prior to time of these photographs) had killed most of the non-sprouting Wyoming big sagebrush from large areas of this range while other areas that had burnt in that wild fire persisted. The unburnt rangeland on which plants of Wyoming big sagebrush persisted were big sagebrush-mixed bunchgrass stepe or savanna whereas the burnt range from which fire had removed big sagebrush was grassland of the wheatgrass-needlegrass mixed or true prairie (arbitrarily depending on interpretation of the vegetation-wise viewer). Likewise, open to interpretation was "naturalness" of the role of fire in removing Wyoming big sagebrush and, hence, composition of the "natural" or "potential natural" (climax) vegetation for this range site-- and, ultimately, for the exact rangeland cover type (Shiflet, 1994). This arbitrary perspective of this range plant community would, in the long run, be time-dependent as Wyoming big sagebrush might, at some point in time, return to the burned range thereby restoring the grassland, the steppe, to a savanna or the big sagebrush shrub-steppe.
Little Bighorn Battlefield National Monument, Big Horn County, Montana. Mid-June- late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem) or, depending on interpretation of sagebrush cover, FRES No. 38 (Plains Grassland Ecosystem). K-49 (Sagebrush Steppe), or, alternatively depending extent of sagebrush cover, K-59 (Wheatgrass-Needlegrass). SRM 612 (Sagebrush-Grass) or, again alternatively, SRM 607 (Wheatgrass-needlegrass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004). Range site: Eastern Sedimentary Plains-Clayey and Shallow Clay Association, 15-19 precipitation zone (Ross and Hunter, 1976, ps. 11-12; Natural Resources Conservation Service, 2013, p. 86). Northwestern Great Plains- Montana Central Grasslands ecoregion 43n (Woods et al., 2002).
79 Fire versus no fire- Thirty years prior to time of these photographs (slides taken in 2013) a wild fire burnt over much of a Wyoming big sagebrush-mixed bunchgrass steppe (a savanna or savanna form of prairie comprised of cespitose grasses) and killed out plants of the nonsprouting Wyoming big sagebrush. The wild fire thereby converted the shrub steppe, a savanna, into a steppe, a grassland or prairie of bunchgrass species.
In the two slides shown here an unburnt portion of the pre-fire Wyoming big sagebrush-mixed bunchgrass savanna was on the left whereas the thirty-year post fire bunchgrass prairie was on the right. Over considerable area of the fired range, Nuttall's sego or mariposa lily was much more abundant than on unburned big sagebrush-bunchgrass savanna.
The overall dominant range plant species in both burned and unburned rangeland was bluebunch wheatgrass, but there were areas with the three dominants (tri-dominants) of bluebunch wheatgrass, green needlegrass, and needle-and-thread. Sideoats grama and blue grama were local associates. All of these grass species were decreasers on this Clayey-Shallow Clay range site. Plains pricklypear was a second woody species. Plains pricklypear was present at about equal apparent density and cover on both burnt and unburnt areas.
It was explained in the immediately preceding caption that interpretation of the composition of this climax range plant community with regard to the "naturalness" of presence or absence of Wyoming big sagebrush and "naturalness" with regard to role of fire in this "natural" range ecosystem was arbitrary and subject to all the inherent biases and perspectives of the range viewer be he range scientist, stockman, naturalist, or general tax-paying citizen.
Obviously, with elimination (for the time being) of the nonsprouting Wyoming big sagebrush, wild fire converted the big sagebrush shrub-mixed grass steppe or savanna to a mixed grass steppe (conversion of savanna to grassland). Is the savanna or the grassland the climax (potential natural) vegetation? If the Wyoming big sagebrush returns at some point in the successional future and restores the sagebrush shrub-steppe, is that state then succession to climax such that the grassland is subclimax or, alternatively, is the sagebrush shrub-steppe a developmental state other than climax? Maybe return of Wyoming big sagebrush is even a brush invasion due to absence of fire ("unnatural" human-maintained fire suppression, perhaps). "Time will tell" if the big sagebrush returns, but this will not answer the question as to what the "real" climax or natural vegetation is. There is probably no escaping some value judgment in this matter. From the standpoint of the Little Bighorn Battle (for which historical purpose this vegetation was being maintained) presence of Wyoming big sagebrush, the big sagebrush mixed grass shrub-steppe, is the "natural" vegetation because that was the vegetation that was here when the arrogant, ego-driven, vain-glorious Custer got what he had coming and drug down largely innocent soldiers with him.
Little Bighorn Battlefield National Monument, Big Horn County, Montana. Mid-June- late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem) or, depending on interpretation of sagebrush cover, FRES No. 38 (Plains Grassland Ecosystem). K-49 (Sagebrush Steppe), or, alternatively depending extent of sagebrush cover, K-59 (Wheatgrass-Needlegrass). SRM 612 (Sagebrush-Grass) or, again alternatively, SRM 607 (Wheatgrass-Needlegrass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004). Range site: Eastern Sedimentary Plains-Clayey and Shallow Clay Association, 15-19 precipitation zone (Ross and Hunter, 1976, ps. 11-12; Natural Resources Conservation Service, 2013, p. 86). Northwestern Great Plains- Montana Central Grasslands ecoregion 43n (Woods et al., 2002).
80. Ultimate composition and structure- Internal structure and species make-up of a Wyoming big sagebrush-mixed grass shrub-steppe in the ridge-ravine relief above the Little Bighorn River Valley in the Northern Great Plains of southeast Montana. Plant species present in the first or upper slide included Wyoming big sagebrush; bluebunch wheatgrass, overall dominant plant; green needlegrass; needle-and-thread; sideoats grama in early green stage; blue grama, short, early leaf stage; and Nuttall's sego or mariposa lily, the major forb on this range. Needle-and-thread and green needlegrass varied from associate species to local tri-dominants with bluebunch wheatgrass.
Range plant species in the second slide indluded two large individuals of bluebunch wheatgrass in foreground with plants of green needlegrass to left and rear of the two plants of bluebunch wheatgrass. Although not readily visible in this slide at this size threre was a pile of horse dung in right background (upper right corner). The range vegetation in these and the following "photoplots" was growing on th outside of a barbed wire fence along a paved road. Pleasure horses on recreational rides occasionally traveled (perhaps grazed) along this route. The mummified dung was probably at least two years old.
Little Bighorn Battlefield National Monument, Big Horn County, Montana. Mid-June- late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem) or, depending on interpretation of sagebrush cover, FRES No. 38 (Plains Grassland Ecosystem). K-49 (Sagebrush Steppe), or, alternatively depending extent of sagebrush cover, K-59 (Wheatgrass-Needlegrass). SRM 612 (Sagebrush-Grass) or, again alternatively, SRM 607 (Wheatgrass-Needlegrass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004). Range site: Eastern Sedimentary Plains-Clayey and Shallow Clay Association, 15-19 precipitation zone (Ross and Hunter, 1976, ps. 11-12; Natural Resources Conservation Service, 2013, p. 86). Northwestern Great Plains- Montana Central Grasslands ecoregion 43n (Woods et al., 2002).
81. Cool composition- Two slightly different views of grass species growing on a Wyoming big sagebrush-mixed bunchgrass steppe, a savanna, in the ridge and ravine topography above the Little Bighorn River Valley in the sedimentary portion of the Northern Great Plains. The major grass species visible (imaginable) here were all bunchgrasses (tufted or cespitose habit). The largest plants were bluebunch wheatgrass with green needlegrass and needle-and-thread growing around the overall dominant species of bluebunch wheatgrass. There were large areas of this range on which these three cool-season, festucoid grasses were tri-dominants (jointly shared dominance); otherwise they were associates to bluebunch wheatgrass. There were some plants of the warm-season, eragrostoid sideoats grama and blue grama. At this season the gramagrasses were in early stages of shoot development. The tan-colored strip in these two "photoplots" was a local population of cheatgrass or downy brome.
The range vegetation seen here was the vernal society of this climax plant community. Sideoats and blue grama would be the dominants of the estival (and, perhaps, part of the autumnal) society, but at peak standing crop of live herbage (as seen in the photographs presented in this Little Bighorn section) the three dominant and/or associate grass species defined the range cover type. Hence, the Sagebrush-Grass (SRM 612) or Wheatgrass-Needlegrass (SRM 607) rangeland cover types (Shiflet, 1994).
Little Bighorn Battlefield National Monument, Big Horn County, Montana. Mid-June- late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem) or, depending on interpretation of sagebrush cover, FRES No. 38 (Plains Grassland Ecosystem). K-49 (Sagebrush Steppe), or, alternatively depending extent of sagebrush cover, K-59 (Wheatgrass-Needlegrass). SRM 612 (Sagebrush-Grass) or, again alternatively, SRM 607 (Wheatgrass-Needlegrass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004). Range site: Eastern Sedimentary Plains-Clayey and Shallow Clay Association, 15-19 precipitation zone (Ross and Hunter, 1976, ps. 11-12; Natural Resources Conservation Service, 2013, p. 86). Northwestern Great Plains- Montana Central Grasslands ecoregion 43n (Woods et al., 2002).
82. Cool customers- Cool-season, festucoid grasses that were dominants (major and defining decreaser species) on a Wyoming big sagebrush-mixed bunchgrass shrub-steppe or, on areas burnt by wild fire that eliminated the big sagebrush, a bunchgrass prairie. These two slides were "photoquadrants" of the grass sward of this climax (potential natural) range plant community. In the first or vertical slide the largest plant was a magnificant specimen of bulebunch wheatgrass with smaller (and more numerous plants) of green needlegrass to its right and immediate rear. The grass sward shown in the second slide had needle-and-thread in left foreground and in much of the rear while two plants of green needlegrass were to left and immediate front of the largest plant which was bluebunch wheatgrass.
There were some now-dead plants of cheatgrass or downy brome that had comparatively small foliar cover. These were visible as the reddish-brown tone. Young (barely emerged) shoots of sideoats grama and blue grama grew sporadically in the sward seen here.
The herbage of this range plant community was at or approaching peak standing crop such that even when the gramagrass species reached maturity in late summer or autumn biomass or herbage yield (that of vernal or autumnal societies) would be less than that present in the vernal society seen here. Thus it was that the rangeland cover type viewed here was dominated by cool-season bunchgrasses: a big sagebrush-bluebunch wheatgrass-needlegrass shrub steppe or, where fire had killed the non-sprouting Wyoming big sagebrush, a bluebunch wheatgrass--green needlegrass--needle-and-thread steppe (bunchgrass prairie).
Little Bighorn Battlefield National Monument, Big Horn County, Montana. Mid-June- late vernal aspect. FRES No. 29 (Sagebrush Shrub Ecosystem) or, depending on interpretation of sagebrush cover, FRES No. 38 (Plains Grassland Ecosystem). K-49 (Sagebrush Steppe), or, alternatively depending extent of sagebrush cover, K-59 (Wheatgrass-Needlegrass). SRM 612 (Sagebrush-Grass) or, again alternatively, SRM 607 (Wheatgrass-Needlegrass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Northwestern Great Plains- Powder River Basin ecoregion 43w (Chapman et al., 2004). Range site: Eastern Sedimentary Plains-Clayey and Shallow Clay Association, 15-19 precipitation zone (Ross and Hunter, 1976, ps. 11-12; Natural Resources Conservation Service, 2013, p. 86). Northwestern Great Plains- Montana Central Grasslands ecoregion 43n (Woods et al., 2002).
Interpretative note: in the absence of Wyoming big sagebrush (or with less cover of sagebrush) this range plant community would be regarded as grassland. In fact, even with this comparative proportion of shrub cover, a case could be made that this range vegetation with scattered shrubs amid bunchgrasses was grassland that had a shrub component. Given the overwhelming dominance of mid-grass species such grassland could probably be most accurately viewed as either true prairie or, with the importance of blue grama (generally a shortgrass species) as northern mixed prairie. Clements (1920, p. 137) gave consociations of needle-and-thread, green neeedlegrass, and blue grama for mixed prairie, but he limited consociations of bluebunch wheatgrass to the bunchgrass prairie which also had a consociation of needle-and-thread (Clements, 1920, p. 150). The bunchgrass prairie (basically the Palouse Prairie) was the Agropyron-Stipa (wheatgrass-needlegrass) Association. As such--and as noted periodically throughout Range Types of North America--the range vegetation presented in this section is a transition grassland that had floristic elements of both the Palouse Prairie (Interior Pacific bunchgrass prairie) and northern mixed prairie Weaver and Albertson, 1954, p. 339-341). Add in Wyoming big sagebrush and this transition grassland became either a savanna form of that ecotonal grassland or, alternatively, the big sagebrush-mixed bunchgrass steppe. Hence, its placement in this location.
Like beauty, categorization of range types (which certainly have their beauty) is in "the eye of the beholder".
83. Still led by the mountain men- Highway sign in central Wyoming describing a wagon route pioneered by the famed mountain man Jim Bridger that crossed part of the Great Plains and went through Bridger Pass in the Rocky Mountains. This rout was shorter than the Oregon Trail and had advantages over the Bozeman Trail. Today, US Highway 20 and 26 follows closerly the Bridger Road.
Overgrazing by horses, mules, and oxen along such trails (miles wide in some streatches) was a major early cause of range deterioration in this phase of the romantic, rigerous era of the Great Frontier, a central defining feature of America. In the section immediately below an example of the sagebrush-shrub steppe--a savanna of Wyoming big sagebrush, needle-and-thread, Sandberg's bluegrass, and threadleaf caric sedge--along the old Bridger Road was presented as yet another example of this rangeland cover type , SRM 612 (Sagebrush-Grass).
84. Range of the frontiersmen- Physiogonomy and structure of a public livestock and game range (Bureau of Land Management allotment) of the big sagebrush shrub-bunchgrass steppe-- a savanna of Wyoming big sagebrush, needle-and-thread, Sandberg's bluegrass, and threadleaf caric sedge--along a part of the Bridger Road in central Wyoming. The county name of Fremont honors the great Trans Mississippi explorer, John C. Fremont. If you students have not already read about, or do not have the time to visit the library and check out (and read) the classic works on Old Gabe (Jim Bridger) and John C. Fremont, the least you can do is "Google 'em". You might also enjoy listening to Johnny Horton sing his tribute to Jim Bridger (on Youtube).
This public (federal) range and its vegetation was shown and described in greater detail in slide-caption sets below. It is likely that this range had a grazing history of abuse dating back to the era of open range ranching. This is not the place to go into the rich, colorful, and, even, thrilling period when Public Domain range such as this was open to the public or "free for the taking" (although some paid with their lives for exercising that tradition). Hollywood enschrined it in public culture and generations world-wide have stopped to re-live one of the most exciting and character-defining moments in human history. This author suggested the following professional historical works (just for starters) related to the Taylor Grazing Act, Grazing Service/Bureau of Land Management, abuse and, finally, the sembalence of proper range management of grazinglands of the Public Domain: Peffer (1951), Calef (1960), Foss (1960), Voigt (1976), and Klemme (1984).
The dominant grass on this degraded range was needle-and-thread with Sandberg's bluegrass and threadleaf caric sedge the associate species. There was considerable plains pricklypear. These species, along with Wyoming big sagebrush, comprise an important part of the climax (potential natural) range vegetation, but the climax dominants are bluebunch wheatgrass, green needlegrass, and Indian ricegrass. These three grass species along with needle-and-thread are decreaser species while Sandberg's bluegrass, threadleaf caric sedge, and Wyoming big sagebrush are increasers (Soil Conservation Service, 1981, p. 27).
Fremont County, Wyoming. Late June; early estival aspect. Bureau of Land Management allotment. FRES No. 29 (Sagebrush Shrub Ecosystem) K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Range site: Loamy, 10-14 inch precipitation zone (Soil Conservation Service, 1981a, p. ). Wyoming Basin- Rolling Sagebrush Steppe ecoregion 18a (Chapman et al., 2004).
85. Not what it once was, but it is still there- A savanna of Wyoming big sagebrush with needle-and-thread as the dominant herbaceous species while Sandberg's bluegrass and threadleaf caric sedge were associates. There were some areas on which Sandberg's bluegrass was the dominant. This range is in a state of range retrogression being in roughly Fair range condition class. Needld-and-thread was the only decreaser species found. Sandberg's bluegrass, threadleaf caric sedge, and Wyoming big sagebrush are increasers; though, of course, all of these range plant species (decreasers and increasers) are components of the climax plant community. It was revealing that the dominant species was a decreaser which indicated that the successional state had not retrogressed extremely low on this sere. Even more revealing to range observers was the fact that there was almost no cheatgrass or downy brome on this range.
Fremont County, Wyoming. Late June; early estival aspect. Bureau of Land Management allotment. FRES No. 29 (Sagebrush Shrub Ecosystem) K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Range site: Loamy, 10-14 inch precipitation zone (Soil Conservation Service, 1981a, p. ). Wyoming Basin- Rolling Sagebrush Steppe ecoregion 18a (Chapman et al., 2004).
86. Fair enough- Internal composition and structure ofa degraded big sagebrush shrub steppe, a savanna of Wyoming big sagebrush, needle-and-thread, Sandberg's bluegrass, and threadleaf caric sedge. Needle-and-thread was the only decreaser on this Loamy range site in the Wyoming Basin. The other three major species in this range plant community were increasers. Of course, beyond a certain proportion of roughly one fifth foliar cover Wyoming big sagebrush is an invader: if and when the savanna becomes a Wyoming big sagebrush shrubland on this range site the range vegetation becomes a brush (noxious woody plants; woody weeds) field.
The climax range vegetation for this Loamy range site was a Wyoming big sagebrush-bluebunch wheatgrass-green needlegrass-Indian ricegrass shrub steppe with these three decreaser grass species comprising 50 to 60 percent of the potential natural plant community (Soil Conservation Service, 1981, p. 27). This rangeland was public (federal) range, a Bureau of Land Management allotment on which there had been no livestock grazing during the current growing season. Undoubted, this range had deteriorated via overgrazing during the open range era prior to official (and enforced) closing of the Public Domain with passage of the Taylor Grazing Act in 1934. It had been three-quarters of a century since there had been at least some semblance of proper grazing management on this range.
This range area was in close proximity to the Powder River or Johnson County range war that raged for five years from 1888-1893 and was quelled only by intervention by the United States Army Cavalry under orders from President Benjamin Henry Harrison (Smith, 1967). For more on the history of the official closure of the Public Domain, Taylor Grazing Act, Grazing Service/Bureau of Land Management, and related aspects of public range administered through the US Department of Interior this author recommended the following sources: Peffer (1951), Calef (1960), Foss (1960), Voigt (1976), and Klemme (1984). It goes without saying that all serious students of Range Management should read the Taylor Grazing Act and the Federal Land Policy and Management Act.
All the learned "old-timers" in the profession of Range Management will tell their students that public range in the United States and Canada (eg. United States range administered by the US Forest Service, US Fish & Wildlife Service, and National Park Service as well as the Bureau of Land Management) has greatly improved with supervision and efforts at scientific management by government agencies along with cooperation (albeit belatedly) of the livstock industry and with inputs from conservationists (including some of the more radical environmentalists). Efforts at range restoration have been and will continue to be involve bitter struggles with long-term commitments from involved stake-holders. Range like that shown and described here has a long way to go to before it is restored (to whatever degree is possible in human time scale), but such range has already come a long way. Range improvement is a grand "success story", but it is far from a completed saga. When man works in cooperation with Mother Nature (and himself) some remarkable things can be accomplished on the range.
remont County, Wyoming. Late June; early estival aspect. Bureau of Land Management allotment. FRES No. 29 (Sagebrush Shrub Ecosystem) K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Range site: Loamy, 10-14 inch precipitation zone (Soil Conservation Service, 1981a, p. 27). Wyoming Basin- Rolling Sagebrush Steppe ecoregion 18a (Chapman et al., 2004).
87. Three big players- Three most important herbaceous species in the herbaceous layer of a Wyoming big sagebrush-shrub steppe or a big sagebrush-bunchgrass savanna. In the first slide two specimens of Sandberg's bluegrass (the two left-most grass plants; amper color) and a single plant of needle-and-thread (one larger, greener tuft of grass) represented the associate and the dominant herbaceous species, respectively. In the second slide needle-and-thread, Sandberg's bluegrass, and threadleaf caric sedge grew so close together that they resembled to be (appeared as if) a single, large, tuft of herbage; threadleaf caric sedge was on the outer right and front of this clump of herbage while needle-and-thread was the tallest shoots and Sandberg's bluegrass was "sandwiched" in between the other two species.
Needle-and-thread was a decreaser whereas Sandbrrg's bluegrass and threadleaf caric sedge were increasers on this Loamy range site in the Wyoming Basin. This public range waas in Fair range condition class. The main three decreaser species of the potential natural (climax) vegetation of this range site were bluebunch wheatgrass, green needlegrass, and Indian ricegrass, none of which were found on this savanna range that had been degraded by overgrazing back in the days of open range (prior to closeing of the Public Doamain with passage of Taylor Grazing Act in 1934).
Fremont County, Wyoming. Late June; early estival aspect. Bureau of Land Management allotment. FRES No. 29 (Sagebrush Shrub Ecosystem) K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Range site: Loamy, 10-14 inch precipitation zone (Soil Conservation Service, 1981a, p. ). Wyoming Basin- Rolling Sagebrush Steppe ecoregion 18a (Chapman et al., 2004).
88. Looking down on some vegetational players- Topdown views of needle-and-thread beside largely dead shoots of Wyoming big sagebrush (first or upper slide) and of threadleaf caric sedge (second slide) in the herbaceous layer of a degraded range that was a big sagebrush shrub-steppe in the Wyoming Basin. This range vegettion consisted of Wyoming big sagebrush with needle-and-thread as the dominant of the herbaceous layer and with Sandberg's bluegrass and threadleaf caric sedge being the associate herbaceous species. There were numerous plants of plains pricklypear.
This public range (BLM allotment) was in Fair range condition class. On this range site needle-and-thread was the only decreaser species remaining, the climax dominants of bluebunch wheatgrass, green needlegrass, and Indian ricegrass had been grazed out. Sandberg's bluegrass and threadleaf caric sedge were increasers as was Wyoming big sagebrush. Plains pricklypear was an obvious invader on this range site.
Given dominance by needle-and-thread it was certainly possible for this public range to slowly improve to perhaps Good condition class. Return of the other three (the main three) decreasers seemed less likely. It seemed probable that the two increasers, which were present as associates, would also have greater cover with proper use of this range so that they too would contribute to improved range condition (to, say, Good condition class).
Conspicuous by its absence from this range was cheatgrass or downy brome, another indication that this degraded range had not retrogressed to Poor range condition class for this range site.
Fremont County, Wyoming. Late June; early estival aspect. Bureau of Land Management allotment. FRES No. 29 (Sagebrush Shrub Ecosystem) K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Range site: Loamy, 10-14 inch precipitation zone (Soil Conservation Service, 1981a, p. ). Wyoming Basin- Rolling Sagebrush Steppe ecoregion 18a (Chapman et al., 2004).
89. Ground layer(s)- Soil surface of a big sagebrush-mixed grass savanna (shrub steppe) in the Wyoming Basin with elk (Cervus canadensis) dung, branches of Wyoming big sgebrush, cladophylls (succulent stems) of plains pricklypear, and several individuals of tumbleweed shield lichen ((Xanthoparmelia chlorochroa= Parmelia chlorochroa).
Animal poisoning by tumblewed shield lichen was discussed above when this fungus-alga mutualistic organism was introduced.
This "photoplot" of the ground layer was on a public range that was in Fair range condition class having undoubtedly had a livestock grazing past of abuse. This abuse was primarily overgrazing in the era of open range (open to anyone and everyone who had livestock) when the Public Domain was overstocked in a free-for-all, no-holds-barred ranching frontier. This public range had not been grazed by cattle or sheep in the current growing season, but the "calling cards" of elk attested to its use as a game range.
Fremont County, Wyoming. Late June; early estival aspect. Bureau of Land Management allotment. FRES No. 29 (Sagebrush Shrub Ecosystem) K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Range site: Loamy, 10-14 inch precipitation zone (Soil Conservation Service, 1981a, p. ). Wyoming Basin- Rolling Sagebrush Steppe ecoregion 18a (Chapman et al., 2004).
Another example of degraded big sagebrush-shrub steppe or the big sagebrush savanna form of Palouse Prairie (one on a more mesic range environment) was presented in the next slide. It was a post card or calendar picture from standpoint of being a pretty secen, but as all rangemen know (or should), "pretty is as pretty does".
90. So what's so great about biodiversity or wildflowers?- A former bluebunch wheatgrass-Idaho fescue-western and thickspike wheatgrass-Wyoming big sagebrush savanna, a big sagebrush-bunchgrass steppe, on a more mesic habitat that had been converted to a Wyoming big sagebrush-Sandberg's bluegrass-Kentucky bluegrass-weed disturbance climax. This disclimax was created initially by livestock overgrazing back in the heyday of open ranch ranching. It was still a grazing disclimax due to on-going overgrazing by cow/calf pairs, but cessation of range burning (= lack of prescription fire) had quite likely augmented range retrogression induced by overgrazing.
The main herbaceous weed (noxious range plant) and the principal wildflower on this range was the native species, silver (or silvery) or tailcup lupine (Lupinus argenteus var. argenteus). The main weed was, of course, Wyoming big sagebrush. Weed is simply any noxious or pest species, plant or animal, native or introduced. Wyoming big sagebrush and tailcup lupine are both native species that are members of the climax range plant community. Both of these native species are increasers for this Clayer-Shallow Clay association range site (Ross and Hunter, 1976, ps. 25-26).
As is the case with so many things in biology from hormones to toxins, the proportion (the "dose") is the difference between proper function or dysfunction, nutrient or poison, even life and death; or in a single word' "health". Beyond the normal variation in cover, density, abundance, etc. of tailcup lupine and Wyoming big sagebrush in the climax vegetation, additional proportions deem these two increaser species weeds (or weed and brush, respectively). Cover, density, frequency, etc. of these increasers below those values found in the climax range plant community also depart the present or existing vegetation away from the climax (retrograde direction or retrogression). Too little or too much of these native species in present range vegetation departs (moves retrograde) the existing range vegetation away from the climax benchmark, though this may be seen as successional movement in "opposite directions". "It is all relative" is the operative maxim with regard to relative amounts (cover, density, biomass) or proportions of plant species in analysis of range condition and trend.
This author has always disliked the term "range health", but when traditionally used in conjuction with other terms "health" conveys a useful concept. Range condition can be defined or described as the ecological (including successional) state, health, and productivity of a range relative to its range site potential (= the potential natural, the climax, vegetation for that particular range site in association with local habitat features). There can be too little or too much of a given plant species on the range relative to the proportion in natural potential range vegetation. This is "range health" viewed as departure from the natural plant community at dynamic equilibrium; plant species composition in relation to that of the climaax vegetation.
Another view of the desirability of a given plant species on the range can just as legitimately be based on economic (rather than ecological) criteria. This is desirability or undesirable (desirable versus undesirable range plants species). Silver or tailcup lupine is a highly toxic range plant, but this is primarily for sheep. Cattle are mostly unaffected by this poisonous nodulated legume. The range in this example served as pasture for cow/calf pairs with these cattle being unaffected (at least noticeably) by presence of tailcup lupine. This is an application of a basic lesson in Principles of Range Management: Cardinal Principle number four is Proper Kind and Class of Range Animal.
So much for the colorful beauty of the aesthetically pleasing, prevalent wildflower (or weed) and for the species diversity seen in this scene. Ecologically and economically speaking, there was a "purty flower" where there ought to have been the "boring" off-green of bluebunch wheatgrass, Idaho fescue, western and thickspike wheatgrass. Remember, "pretty is as pretty does". In this instance, however, the pretty weed or wildflower allowed the ole range professor to teach a basic lesson. Maybe silver lupine was pretty afterall; the status of weed or wildflower remained the option of the onlooker.
Meagher County, Montana. Late June. FRES No. 29 (Sagebrush Shrub Ecosystem) K-49 (Sagebrush Steppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1989, p. 40) was Mixed Grass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 of Cold Temperate Grassland 142, but this was Great Plains not Great Basin. Range site: Foothills and Mountains- Clayey and Shallow Clay association, 15-19 inch precipitation zone (Ross and Hunter, 1976, ps. 25-26). Northwestern Great Plains- Shield-Smith Valleys ecoregion 43t (Woods et al., 2002).
91. Wide and widespread silver- Two plants of silver (or silvery) or tailcup lupine (Lupinus argenteus var. argenteus) on Palouse Prairie-Northern Great Plains transition grassland in central Montana. Silver lupine is one of the most widely distributed Lupinus species in North America extending from the Southern Great Plains of the Plains States up through the Prairie Provinces and British Columbia. Silver lupine is adapted to a wide array of habitats and grows on grasslands, forests, parklands, sagebrush-grass savannahs, and up to alpine (Hermann, 1966, ps. 103-104; Lesica, 2012, p. 310). In keeping with this wide adaptation, a number varieties and great variability within the species (Great Plains Flora Association, 1986, p. 463) have been reported for L. argenteus. Lesica (2012, ps. 310-311) described four varieties in Montana. Some authorities (eg. Burrows and tyrl, 2013, ps. 571-572) include L. caudatus in the L. argenteus group.
Silvery lupine has a large caudex or proaxis (a semi-woody base of herbaceous plants; the union of root and shoot near or slightly below the soil surface) from which a number of shoots arise (Great Plains Flora Association, 1986, p. 463; Lesica, 2012, p. 310). This morphological festure was conspicuous in the two above photographs.
The Lupinus genus is a challenging one even (maybe, especially) for taxonomists given integradation and variation within the large number of species. Lupinus is also one of the more important group of species from standpoint of sheep poisoning on the range. Although Lupinus species furnish forage for livestock and wildlife (Hermann, 1966, 103) a number of species of this papilionaceous legume can be highly toxic. Borrows and Tyrl (2013, ps. 567- 576) provided the most recent definitive treatment for Lupinus toxicity (at time of this writing) and noted that there are approximately 150 Lupinus species (not to even begin with subspecies and varieties) in North America most of which have not been been studied with ragard to poisonous principles.
The toxic principle in North American Lupinus species is a group of quinolizidine alkaloids, the main two of which are lupanine and anagyrine, that cause acute neurological, hepatic, and renal disorders--a classic syndrome--and, in some instances, a reproductive malady known as crooked calf disease that induces abortion, or deformed fetuses. The disease-causing substances, the alkaloids, are produced through chemical transformation by a fungus (Phomopsis leptostromiformis= Diaporthe toxica). Lupinosis, the generic term for Lupine-induced toxicity, is most serious in sheep, but it also affects goats, cattle, and horses. Tetragenic effects are most important in cattle. order Again, Borrows and Tyrl (2013, ps. 567- 576) is the definitive source though, of course, Kingsbury (1964. ps. 333-341), while limited by its earlier date, will always be an old, revered standby. In fact, the quinolizidine alkaloids had been implicated as the causative principle even back at the time of Kingsbury (1964, p. 333-334).
L. argenteus contains both alkaloid types--lupanine and anagyrine--and is one of the more widely studied, including feeding trials, poisonous lupines (Burrows and tyrl, 2013, ps. 571-575) in regards to livestock poisoning. Strickingly beautiful, but deadly under certain conditions. One of the main one of these is sheep consuming mature or maturing legumes (fruits) of lupines or when hungry and being driven through lupine-endowed ranges.
Meagher County, Montana. Late June; full-bloom phenological stage.
92. Silvery shoots- Shoots, including leaves and infloresecences, of silvery lupine growing on lush bluebunch wheatgrass-Idaho fescue transition from Palouse Prairie to Northern Great Plains mixed prairie--grassland in the dissected plains area of northcentral Wyoming. Lesica (2013, p. 310) interpreted the inflorescence of Lupinus species as a raceme.
Sheridan County, Wyoming. Mid-June; peak-bloom phenological stage.
93. Silverish green- This sunlite view of the spreading leaves with their six to eight leaflets of silvery lupine showed off the basis of the common name for this species. This was one of several plants growing on a bluebunch wheatgrass-Idaho fescue-dominated grassland in the dissected plains portion of the Northern Great Plains in northcentral Wyoming.
Sheridan County, Wyoming. Mid-June.
94. Flowers and fruits in the hills- Papilionaceous flowers along a portion of a raceme (upper slide) and just-starting to -ripen legumes (second slide) of silvery lupine growing with bluebunch wheatgrass and Idaho fescue of a transition--from Palouse Prairie to Northern Great Plains mixed prairie--in the dissected plains area of the Northern Great Plains in northcentral Wyoming.
The legumes, especially their seeds, are one of the most poisonous parts of this beautiful and, too often, deadly range forb.
Sheridan County, Wyoming. Mid-June.
95. Mixed savanna on a hillside- A tree-shrub-mixed grass savanna on a hill slope in the Big Horn Basin of northcentral Wyoming. Various species of cool-season grasses--bluebunch wheatgrass was overall dominant with needle-and-thread, western wheatgrass, and blue grama local associates--along with scattered shrub-sized trees of Utah juniper (Juniperus osteosprema= J. utahensis) and Wyoming big sagebrush made up a savanna on the west slope of a low hill. The grass-dominated herbaceous layer (there were essentially no forbs present) was a mixture of both warm- and cool-seaon grasses (bluebunch wheatgrass, needle-and-thread, and western wheatgrass were cool-season species) as well as of bunchgrasses (bluebunch wheatgrass, needle-and-thread, and blue grama were cespitose grasse species) and turfgrasses (western wheatgrass was the sod-forming grass species).
This savanna community served as pasture for both cattle and horses although no animals of either species were present during the current growing season.
The limited presence of Utah juniper might have been due--at least partly--to a relatively recent fire that left a few charred stumps of this conifer, but as was shown in some slides below, Utah juniper formed a woodland (actually, nore of a shrubland) in a shallow ravine or coulee about 400 yards from the savanna vegetation presented in these three photographs.
Hot Springs County, Wyoming. late June; early estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K- 50 (Wheatgrass-Needlegrass- Shrubsteppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Great Basin Shrub-Grassland 142.2, Wheatgrass Series 142.21. Wyoming Basin- Big Horn Basin ecoregion 18b (Chapman et al., 2004).
96. Two zones of a savanna- Grass layer (both slides) and shrub layer (second slide) of a Utah juniper-Wyoming big sagebrush-mixed grass savannah on a hillside in Big Horn Basin of northcentral Wyoming. The grass species included the dominant bluebunch wheatgrass and, as local associates, westrn wheatgrass, needle-and-thread, and blue grama. Thus the grass-defined, grass-dominated herbaceous layer was a mixture of sod-forming or turf grasses and cespitose grasses (bunchgrasses) as well as cool-season and warm-seson grasses. There was some minor cover of cheatgrass or downy brome. The silver-colored shrubs in the second slide were Wyoming big sagebrush.
This climax plant community had been a range for beef cattle and horses, but in the present growing season neither species was present on this natural pasture.
Hot Springs County, Wyoming. late June; early estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K- 50 (Wheatgrass-Needlegrass- Shrubsteppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Great Basin Shrub-Grassland 142.2, Wheatgrass Series 142.21. Wyoming Basin- Big Horn Basin ecoregion 18b (Chapman et al., 2004).
97. Herbaceous zone of a savanna- The herbaceous layer of a Utah juniper-Wyoming big sagebrush-mixed grass savanna in the Big Horn Basin of northcentral Wyoming. The large cespitose (tufted or bunched) grass plants were mostly bluebunch wheatgrass with some needle-and-thread. Blue grama, the major warm-season grass of this range, had not reached much shoot height at this point in the warm-growing season. The rhizomatous western wheatgrass formed a sod turf in large patches such as the one in the mid-ground of the first slide. This was a mixed grass herbaceous layer given presence of both cool-season and warm-season and cespitose and a major turf (sod-forming) species in western wheatgrass. (By the way, western wheatgarass is the State Grass of the Equality State.)
The physiogonomically prominent bunchgrass aspect of the herbaceous layer is the characteristic feature defining a steppe and, in this instance, of a steppe savanna.
Hot Springs County, Wyoming. late June; early estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K- 50 (Wheatgrass-Needlegrass- Shrubsteppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Great Basin Shrub-Grassland 142.2, Wheatgrass Series 142.21. Wyoming Basin- Big Horn Basin ecoregion 18b (Chapman et al., 2004).
98. Where it was more moist- A draw, coulee or shallow ravine on a hillside in the Big Horn Basin served as a Utah juniper woodland or, given small size of conifers, a shrubland that was surrounded by a Utah juniper-Wyoming big sagebrush-mixed grass savanna that was shown and dscribed immediately above. A wild fire had burned on the left side of the Utah juniper shrubland with some charred stumps of this conifer left as evidence. More abundant plants of Utah juniper and absence of burnt stumps indicated that there had not been a recent fire on the right side of the Utah juniper dominated range plant community.
Hot Springs County, Wyoming. late June; early estival aspect. For the Utah juniper woodland: FRES No. Pinyon-Juniper Shrubland Ecosystem. K- 21 (Juniper-Pinyon Woodland). Closest SRM was 412 (Juniper-Pinyon Woodland) or 504 (Juniper-Pinyon PineWoodland). Closest biotic community for Utah juniper woodland was in Brown et al. (1998, p.38) was Great Basin Conifer Woodland 122.7, Pinyon-Juniper Series 122.71. For the sagebrush-grass savanna: FRES No. 29 (Sagebrush Shrubland Ecosystem). K- 50 (Wheatgrass-Needlegrass- Shrubsteppe). SRM 612 (Sagebrush-Grass). Closest biotic community in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Great Basin Shrub-Grassland 142.2, Wheatgrass Series 142.21. Wyoming Basin- Big Horn Basin ecoregion 18b (Chapman et al., 2004).
99. Three specimens- Three shrub-size examples of Utah juniper (Juniperus osteosperma) that grew on a Wyoming big sagebrush-bunchgrass (bluebunch wheatgrass, the dominant) shrub steppe or savanna at edge of Big Horn Basin. Utah juniper is one of up to six or seven major Juniperus species in the pinyon pine (Pinus spp.)-juniper (Juniprus spp.) woodland that sprawls over millions of acres western North America (especially west of the 98th meridian). The pinyon pine-juniper woodland is contiguous with other range types including the Palouse Prairie, Wyoming big sagebrush-bunchgrass shrub steppe, and the Great Basin Desert. Utah juniper grows widely and prolificantly over such a vast region (or parts of several regions) that it has to get "top-billing" as a "supporting actor" in several range cover types.
Occurrence of Utah juniper on this big sagebrush-bunchgrass steppe or savanna provided an opportune momement to include Utah juniper within this treatment of Nortth American range types which tried to be as comprehensive as possible. The smaller grey or silverish-colored plants such as the one in lower left corner in the third or lowermost slide were plants of Wyoming big sagebrush. A number of these were small (thus, presumedly young) plants were growing in portions of this savanna.
Hot Springs County, Wyoming. Late June.
100. Flesh and foliage- Needles and fleshy cones of Utah juniper on a Wyoming big sagebrush-bluebunch wheatgrass shrub steppe in foothills at edge of Big Horn Basin. Seed cones of Utah juniper are single-seeded and require one up to two years for maturity of this structure (Lesica, 2012). Unlike most Juniperus species, J. osteosperma is monoecious.
For whatever reasons, there are not in-depth or monographic treatments of the biology, ecology, silvics, etc. of Utah juniper as there are for some of the othr imortant Juniperus species.
Hot Springs County, Wyoming. Late June; seeds approaching maturity.
101. Beauty in reproduction- Spikelets at peak anthesis on spike of western wheatgrass. The time period over which anthers are exerted in spikelets of western wheatgrass is unbelieveably brief. The notable "yawning" gap in spikelets shown, with both stigmas and anthers were so clearly visible, lasted only one day. These opened one morning, where photographed that afternoon, and by next morning were closed with anthers withered and stigmas atrophied.
Not all spikes in a population of western wheatgrass have their spikelets open at the time. Some shoot have spikes with spikelets open and at anthesis on one day and other shoots have spikes at anthesis on another day, but sexual organs are open to the extra-floret world for a remarkably short span of time. That is a commonly found pattern of sexual reproduction in range plants, especially on harsh habitats.
These spikelets were doing their thing on the Wyoming big sagebrush-bluebunch wheatgrasss range in foothills at edge of Big Horn Basin featured above.
Hot Springs County, Wyoming. Late June; peak anthesis (flowering) stage.
102. An annual alien- Corn brome (Bromus squarrosus), another naturalized, Eurasian, annal grass, was much less common than B. tectorum on the foothill Wyoming big sagebrush- juniper range featured above, but it was common on locally disturbed microsites and in association with local colonies of western wheatgrass.
Hot Springs County, Wyoming. Mid-June; peak standing crop, hard-dough grain phenological stage.
103. Business end of an annual alien- Large drooping spikelets on panicles of corn brome. At peak standing crop most of the biomass of this little annual was in its heavy fruit-bearing spikelets. Eye-catching little guys though obviously of limited feed value (except for granivores like rodents and certain birds).
Hot Springs County, Wyoming. Mid-June; hard-dough grain phenological stage.
104. A sometime dominant- Sheep or Rocky Mountain fescue (Festuca ovina var. rydbergii= F. saximontana=F. brachyphylla subsp. saximontana) was the dominant of a bunchgrass-Wyoming big sagebrush savanna or shrub steppe in Powder River Basin of eastern Wyoming.
Sheep fescue is one of the larger, ranker-growing grasses on the mixed prairie of the Front Range of the Central Rocky Mountains as well as in habitats in the Powder River Basin. was sheep fescue and for which the scientific name Festuca ovina var. rydbergii was used in Grasses of Wyoming (Skinner et al., 1999, p. 66, 68). This author-photographer did not encounter this species as other than a local dominant. Clements (1936, p. 258) interpreted Festuca ovina as one of eight perdominants, widespread dominants that bind associations together into climaxes or, the synonym, formations) (Clements, 1936, ps. 258, 271). Some of the other perdominants that bound the five grassland associations into the climax were needle-and-thread, western wheatgrass, blue grama, sand dropseed, and Junegrasss (Clements, 1936, p. 258). However, Clements (1920) used F. ovina as an "umbrella species" to include the widespread F. idahoensis. This usage was consistent with the taxonomy and nomenclature of that time as, for example, in Coulter and Nelson (1909, p. 75) and as explained in Barkworth et al. (2007, p. 422).
This is one of the most confused grass species in the Northern Great Plains. It was interpreted in Grasses of Wyoming (Skinner et al., 1999, p. 66, 68) as sheep fescue with the scientific name, Festuca ovina var. rydbergii. The most recent and presumedly most authoritative (though not necessarily synonymous with most taxonomically correct) treatment of F. ovina was that in Barkworth et al. (2007, ps. 428-432) in which F. ovina was was restricted to a species introduced into North America from Eurasia so that it was necessary to "transplant" all native forms, variants, etc. previously included with F. ovina into other Festuca species and subspecies. Into which of these one or more species and/or subspecies F. ovina var. rydbergii belongs was not explained in Barkworth et al. (2007, p. 422). If F. ovina var. rydbergii was "transplanted" according to the taxonomic organization in Flora of North America it seemed that F. saximontana or F. brachyphylla were the most likely candidates. Or perhaps the older taxon of F. brachyphylla subsp. saximontana was more likely to be the correct taxon for F. ovina var. rydbergii. Hitchcock and Chase (1951, p. 74) showed F. saximontana as an earlier binominal for F. ovina. Kaul et al. (2006, p.676) used F. saximontana for specimens in the far western Nebraska Panhandle that had previously been identified as Festuca ovina var. rydbergi, but Skinner et al. (1999, p. 67-68) retained (Festuca ovina var. rydbergi for specimens and plants on Wyoming range up to subalpine elevations. For the Prairie Privinces, Looman and Best (1987, p. 131) recognized F. ovina var. saximontant noting that it was "[a] variable species which has been divided into several varities and forms". In the most recent treatment (as of this writing) the most recent treatment for Montana (Lesica, 2012, p. 682) put Rocky Mountain fescue (F. saximontana) along with such other taxa as F. ovina var. brevifolia and F. brachyphylla as forms of Idaho fescue (F. idahoensis).
What a mess! Too much so for this simplier- and more practical-minded rangeman.
Whatever the most nearly scientifically correct scientific name, this is a large, conspicuous fescue of one or another species that was the dominant of a bunchgrass-Wyoming big sagebrush savanna.
Natrona County, Wyoming. Mid-June- peak anthesis phenological stage.
105. Threads of a widespread and improtant one- Threadleaf caric sedge (Carex filifolia) is arguably the most important Carex species over dryland range in western North America. Unlike many, if not most, of the Carex species threadleaf acric sedge is not a range plant of mesic or hydric habitats. While many Carex species are restricted to wetland environments such as riparian zones or floodplains C. filifolia calls dry uplands on wind-swept plains its preferred habitat.
Threadleaf sedge is usually not a dominant, but is instead an important associate species to such dominants as bluebunch wheatgrass, Idaho fescue, western wheatgrass, blue grama, Junegrass, needle-and-thread, and so forth. Like most of these associated species threadleaf caric sedge "cures on the vine" meaning that its herbage retains a high level of nutrients and remains preferrred forage during dormancy such as throughout much of winter. Threadleaf caric sedge is on the famed International Range Plant Identification Contest sponsored by the Society for RangeManagement (Stubbendieck et al., 1992, ps 326-327).
Good sources for treatment of this important range plant include the timeless Range Plant Handbook (Forest Service, 1941, GL5). Another classic for treatment of the caric sedges remains Hermann (1970) and the revised field guide of Carex species by Hurd et al., (1998, esp. ps. 112-113) plus various regional publications such as one for the Pacific Northwest (Wilson et al., 2008, ps. 172-173).
Bureau of Land Management allotment, Fremont County, Wyoming. Late June; mature-achene stage, plant entering dormancy.
106. Big example of a common (and important) one- Large plant of scarlet globe mallow (Sphaeralcea coccinea) growing on a Wyoming big sagebrush-bunchgrass savanna (shrub steppe savanna) was shown in first slide. The econd slide presented a view of individual flowers showing the prominent staminal column. Scarlet globe mallow is one of the more widespread and, suppossedly, palatable range forbs throughout much of the Great Plains and eastern parts of adjoining provinces. This member of the mallow family (Malvaceae) is one of the 200 species on the International Intercollegiate Range Plant Ideitification Contest sponsored by the Society of Range Management (Stuppendieck et al., 1992, ps. 378-379).
These authors reported that scarlet globemallow has Excellent forage value for native ruminants like deer and pronghorn yet only Fairl to Worthless in forage value for livestock, especially in the Great Plains where it is grazed but infrequently (Stubbendieck et al., 1992, ps. 378-379). Scarlet globe mallow was deemed important enough for a short discussion in Notes on Western Range Forbs (Hermann, 1966, ps. 179-181)
Bureau of Land Management allotment, Fremont County, Wyoming. Late June; peak-bloom phenological stage.
107. A bitter species- Stemless bitterweed (Hymenoxys acaulis) on a Wyoming big sagebrush-grass savanna in the Wyoming Basin. Burrows and Tyrl (2013, 177-178) noted that there were 17 Hymenoxys species in North America, but only five of these are poisonous plants. H. acaulis is NOT one of the five. Instead, this is just another DYC (Damn Yellow Composite) growing on the range providing some pleasure to the senses (tongues of insects and eyes of humans).
Johnson County, Wyoming. Mid-June; full-bloom stage.
108. Lily on the prairie and the steppe- Topdown view--that was thoroughly messed up by Espon Perfection 600 scanner--(first, horizontal, or upper slide) and side view (second or vertical slide) of Nuttall's sego lily or mariposa lily (Calochortus nuttallii) growing on a sheep fescue (Festuca ovina var. rydbergii= F. saximontana=F. brachyphylla subsp. saximontana)-Wyoming big sagebrush savanna or shrub steppe (first slide) and a on a bluebunch wheatgrass-green needlegrass bunchgrass mixed prairie (second slide).
Nuttall's ssego lily is a a monocot forb of fairly wide distribution across the central grasslands and shrub steppe savanna of northern North America. Several of the Calochortus species closely resemble each other and have overlapping species (biological) ranges, especially C. nuttallii and Gunnisons's mariposa lily or sego lily (C. gunnisoni). C. gunnisoni was featured elsewhere in this web publication: on northern mixed prairie in the chapter of that name.
The definitive source for the Calochortus species is Gerritsen and Parsons (2007).
Natrona County, Wyoming (first or horizontal slide) and Big Horn County, Montana (second or vertical slide). Mid-June; peak-bloom phenological stage.
109. Beautiful no matter which direction- Sideview of inflorescence and upper shoot (apex of sexual shoot) of Nuttall's mariposa or sego lily growing on a sheep fescue-Wyoming big sagebrush shrub steppe (savanna) in the Powder River Basin of eastern Wyoming.
Natrona County, Wyoming. Mid-June- full-bloom phenological stage.
110. "They don't come any purtier"- Topdown view into the dazzlingly beautiful flower of Nuttall's sego lily or Nuttall's mariposa lily growing on a sheep fescue-Wyoming big sagebrush shrub steppe (or savanna) in the Powder River Basin of eastern Wyoming.
Natrona County, Wyoming. Mid-June- full-bloom phenological stage.
111. A little but interesting forb- Dwarf stickleaf or dwarf blazing star (Mentzelia pumila) at edge of a ponderosa pine woodland and Wyoming big sagebrush-bluebunch wheatgrass savanna in the sedimentary hills above the Townsend Basin in the Northern Rocky Mountains of westcentral Montana.
Mentzelia species are in the loasa or blazing star family (Loasaceae). In fact, Mentzelia is the sole genus of Loasaceae in states like Montana (Lesica, 2013, ps. 173-`74), and there is only one other genus in Loasaceae in New Mexico (Allred and Ivey, 2012, p, 384-387) and the greater Great Plains Region (Great Plains Flora Association, 1986, ps. 269-273).
Lewis & Clark County, Montana. Late June; peak-bloom phenological stage.
112. Interesting leaves- Deeply dissected or laciniate leaves of dwarf stickleaf or dwarf blazing star. These leaves were on the plant presented in the immediately preceding slide. The common name of stickleaf was derived from the presence of barbed pubescence on leaves that results in leaves adhering to things such as clothing, hair, etc. This sometimes results in contamination of wool fleeces and similar nusiances (like the bloody leaves crawling up one's pants legs).
Lewis & Clark County, Montana. Late June;
113. Gold in the hills- These flowers were on the plant of dwarf stickleaf or dwarf blazing star presented two slide/caption sets above. It was growing at the edge of a ponderosa pine woodland and Wyoming big sagebrush-bluebunch wheatgrass savanna in the sedimentary hills above the Townsend Basin in the Northern Rocky Mountains. Mentzelia species have some of the most conspicuous flowers of all dicotyledous forbs in Norrth Amrica, and these flowers typically have solid-colored petals of lighter colors (no ornate or complex color pattern).
The combination of large, shapely petals along with prominent anthers and stigmas makes for picturesque blooms on grasslands where the simple green, yellows, and browns of grass herbage lend a "monotous" color to range plant communities for all but rangemen and true prairiemen. Even in the diverse range vegetation of ponderosa pine, Wyoming big sagebrush, and large bunchgrasses M. pumila had a prominent presence.
Lewis & Clark County, Montana. Late June; peak-bloom phenological stage.
114. Ultimate in beauty for a range forb- Young plant (young floral buds, any) of bittersroot in first slide and details of an open, an opening, and two unopened floral buds in second slide.
115. Most striking state flower- Bitterroot, the Montana State Flower, is arguably the most brilliant, eye-catching, and charming forb that has the distinction of being a state flower.
The big sagebrush shrub steppe is far from uniform but it is remarkably consistent in physiogonomy, structure, and composition throughuot the various physiographic provinces of which it is a major range cover type, a zonal climax. In the Colorado Plateau big sagebrush is represented by its three major subspecies: 1) basin big sagebrush (Artemisia tridentata subsp. tridentata), Wyoming big sagebrush (A. t. subsp. wyomingensis), and 3) mountain big sagebrush (A. t. subsp. vaseyana).
The examples of big sagebrush shrub steppe in the Colordo Plateau were from eastern Utah and were principally of the Indian riecgrass (Oryzopsis hymenoides) form or subtype.
116. Four principal species of the basin form- Relict vegetation on an upper part of a local basin (depression) on which a big sagebrush-bunchgrass savanna had developed. Thr four major species on this gently sloping savanna range were basin big sagebrush, four-wing saltbush (Atriplex canescens), Indian ricegrass, and Nelson's or Columbia needlegrass (Stipa nelsonii= S. columbiana).
The only shrubs that were readily distinguishable in these two slides were basin big sagebrush.
This range was part of a long-abandoned homestead. It had not been acessible to livestock for a number of years, but was open to mule deer and smaller mammals such as black-tailed jackrabbit (Lepus californicus) as well as insects (including harvester ants as shown below). It provided an outstanding example of the climax range vegetation for this general area of southeastern Utah with the exception of having some annual exotic species.
San Juan County, Utah. Late July; early estival aspect. FRES No.
29 (Sagebrush Shrubland Ecosystem). K- 49 (Sagebrush Steppe). SRM 401 (Basin
big Sagebrush). Closest biotic community in Brown et al. (1998, p. 40) was Cold
Temperate Grassland 142, Great Basin Shrub-Grassland 142.2, Ricegrass Series
142.23. Colorado Plateaus- Semiarid Benchlands and Canyonlands Ecoregion 20c
(Woods et al., 2001).
117. Four big actors- A "photoplot" of part of a shrub-bunchgrass savanna that is more commonly described as a shrub-steppes in the Colorado Plateau of southeastern Utah. The four major range plant species were Indian ricegrass Nelson's or Columbia needlegrass, fourwing saltbush and basin big sagebush.
This was the climax (potential natural) vegetation for this habitat seen here at peak standing crop.
San Juan County, Utah. Late July; early estival aspect. FRES No.
29 (Sagebrush Shrubland Ecosystem). K- 49 (Sagebrush Steppe). SRM 401 (Basin
big Sagebrush). Closest biotic community in Brown et al. (1998, p. 40) was Cold
Temperate Grassland 142, Great Basin Shrub-Grassland 142.2, Ricegrass Series
142.23. Colorado Plateaus- Semiarid Benchlands and Canyonlands Ecoregion 20c
(Woods et al., 2001).
118. Not quite so mint, but still notable- Part of the shrub-bunchgrass savanna range shown in the two immediately preceding slide/caption sets. Featured in these nested 'photoplots" (the second slide a subset of the first slide) was a den or nest of western harvester ants (Pogonomyrmex occcidentalis) surrounded by Indian ricegrass, Nelson's or Columbia needlegrass, downy brome or cheatgrass (Bromus tectorum), and fourwing saltbush.
The western harvester ant den entrance was visible as the bare spot in center midground of the first (upper) slide and in right foreground of the second slide. The conspicuous forb surrounding the bare area of the den was the annual sunflower known as the lesser or prairie sunflower (Helianths petiolaris).
San Juan County, Utah. Late July; early estival aspect. FRES No.
29 (Sagebrush Shrubland Ecosystem). K- 49 (Sagebrush Steppe). SRM 401 (Basin
big Sagebrush). Closest biotic community in Brown et al. (1998, p. 40) was Cold
Temperate Grassland 142, Great Basin Shrub-Grassland 142.2, Ricegrass Series
142.23. Colorado Plateaus- Semiarid Benchlands and Canyonlands Ecoregion 20c
(Woods et al., 2001).
119. Lots of shrub species and a lot of grass- On low foothill just below a pinyon pine (Pinus edulis)-juniper (Juniperus spp.) woodland this sagebrush-bunchgrass steppe constituted a shrub-grass savanna that could be envisioned as an ecotone or transition zone between a mixed prairie, a semiarid grassland, and a big sagebrush form of cold desert. Shrub species appeared to include both Wyoming big sagebrush (primarily) and mountain big sagebrush (secondarily) as dominant(s) along with Bigelow's sagebrush or flat sagebrush (Artemisia bigelovii) and green Mormon tea or green joint-fir (Ephedra viridis viridis). Important grass species included the dominant needle-and-thread (Stipa comata), Indian ricegrass, blue grama (Bouteloua gracilis), and galleta (Hilaria jamesii) in that relative order of cover. Forbs were very limited (and limited primariy to) wooly plantain (Plantago patagonia).
These herbaceous sspecies were predominantly those of the Great Plains mixed prairie and shortgrass plains types. In effect this Colorado Plateau was a broad transition zone--that is, a vast ecotone--between Great Plains grassland and Great Basin cold desert (a sagebrush-dominated shrubland).
San Juan County, Utah. Late July; early estival aspect. FRES No. 29 (Sagebrush
Shrubland Ecosystem). K- 49 (Sagebrush Steppe). SRM 403 (Wyoming Big Sagebrush).
Closest biotic community in Brown et al. (1998, p. 40) was Cold Temperate Grassland
142, Great Basin Shrub-Grassland 142.2, Mixed Shrub-Bunchgrass Series 142.22.
Semidesert Sandy Loam range site. Colorado Plateaus- Semiarid Benchlands and
Canyonlands Ecoregion 20c (Woods et al., 2001).
120. Low shrubs and lots of grass-
San Juan County, Utah. Late July; early estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K- 49 (Sagebrush Steppe). SRM 403 (Wyoming Big Sagebrush). Closest biotic community in Brown et al. (1998, p. 40) was Cold Temperate Grassland 142, Great Basin Shrub-Grassland 142.2, Mixed Shrub-Bunchgrass Series 142.22. Semidesert Sandy Loam range site. Colorado Plateaus- Semiarid Benchlands and Canyonlands Ecoregion 20c (Woods et al., 2001).
Location note: a Great Plains composition grassland- mixed shrub savanna in the general area of the above sagebrush-bunchgrass steppe was presented in chapter, shrubLow or dwarf sagebrush-dominated (or -defined) range types- Across much of the sagebrush steppe low or dwarf sagebrush (Artemisia arbuscula) cover types are second in importance to those of big sagebrush. For steppe vegetation in the Columbia Basin province (Franklin and Dyrness, 1973, ps. 211, 218, 219, 224) recognized Artemisia tridentata range communities as zonal associations that often existed as climatic climaxes. Associations of these same species (the same species-designated names or titles of communities) in the High Lava Plains province were not designated as zonal but instead were sometimes interpreted as topographic or topoedaphic climaxes or, in other cases, as being "very similar" to those of the Columbia Basin associations (Franklin and Dyrness, 1973, ps. 236, 238).
The Artemisia arbuscula communities of the sagebrush steppe in California were described by Young et al. in Barbour and Major, 1995, ps. 776-778, 780-781). Many of these low sagebrush range communities were identified and described for the Modoc Plateau of the Basin and Range province. Curiously, the Modoc Plateau and Warner Mountains were not described in standard references on physiographic provinces (eg. Fenneman, 1931).
The Artemisia arbuscula associations of the High Lava Plains province were viewed by Franklin and Dyrness (1973, ps. 239-241) as edaphic climaxes that developed (were found) with Artemisia tridentata communities. There was a mosaic of climax range vegetation made up of these associations which, in some locations, included also the Artemisis cana-dominated communities. Young et al. in Barbour and Major (1995, p. 780) specified these same conclusions or interpretations.
Franklin and Dyness (1973, p. 239) recognized the Artemisia arbuscula/Festuca idahoensis and Artemisia arbuscula/Agropyron spicatum associations as two widespread and important low sagebrush range communities in south- central and southeastern Oregon. Young et al. in Barbour and Major (1995, ps. 776-778) described these same (or very similar) communities for northeastern California as well as an Artemisia arbuscula/Stipa thurberiana community. Again, all of these were regarded as edaphic climaxes within the larger climatic climaxes of Artemisia tridentata associations.
This was consistent with the Tanslian polyclimax theory. Low sagebrush vegetation could also be viewed as preclimax to the big sagebrush climax consistent with the Clementsian monoclimax theory. Or, perhaps more logically, low sagebrush is postclimax given that this species "occupies the oldest land surfaces in the Artemisia environment" (Young et al. in Barbour and Major, 1995, p. 781). In the context of Landscape Ecology low sagebrush-dominated communities are patches within the matrix of big sagebrush vegetation. What mind games range vegetation affords!
119. Low or dwarf sagebrush (Artemisia arbuscula) range- This relatively depleted (cause of retrogression unknown) range vegetation was an example of the Artemisia arbuscula/Festuca idahoensis association. Idaho fescue was often lacking in intershrub spaces, but it was the dominant grass around edges of low sagebrush plants. Sandberg bluegrass was the most common grass, but its overwhelming domination by Idaho fescue near protection of low sagebrush indicated that the latter not the former was the potential natural dominant. The dominant herbaceous species was slenderbush wild buckwheat (Erigonum microthecum). Annual species like the naturalized cheatgrass or downy brome (Bromus tectorum) and tansy mustard (Descurainia pinnata) were absent to rare if present at all.
This general view showed the spatial arrangement of "patches" of low sagebrush communities within the larger or general big sagebrush vegetation. The latter was visible in the background (upper left across to upper right corner). Physiognomy of low sagebrush-dominated range vegetation was obvious.
Note rocks on ground surface of this example of the low sagebrush type (this was shown in more detatil in two succeeding photographs). Franklin and Dyrness (1973, p. 239) specified that both of the major Artemisia arbuscula associations "typically occur with Artemisia tridentata communities as edaphic climaxes on shallow, stony phases of the zonal Haploxerolls (Brown soils)". Young et al. in Barbour and Major (1995, p. 780) repeated verbatim the last part of that sentence. Both of the phenomena described by Franklina nd Dyrness (1973, p. 239) were visible in this example of the low sagebrush-Idaho fescue association.
Burns District, Bureau opf Land Management, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 406 (Low Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Low sagebrush/Idaho fescue association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
120. "Inside" a low sagebrush range community- Spatial arrangement and structure of an example of the Artemisis arbuscula/Festuca idahoensis association in deteriorated range condition. Almost no grass present except for widely scattered individuals of Sandberg bluegrass and (fewer yet) Idaho fescue plants in shelter of some low sagebrush. The associate species was slenderbush wild buckwheat. The close proximity of the dominant and associate species was visible in lower left foreground. This was shown closeup in photographs presented below.
Cheatgrass was almost totally absent.
High Lava Plains province (Franklin and Dyrness, 1973, ps. 6, 32-34) corresponding to Harney section of Columbia Plateau physiographic province (Fenneman, 1931, ps. 236, 272-273).
Burns District, Bureau of Land Management, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 406 (Low Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Lowe sagebrush/Idaho fescue aassociation of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
121. Low sagebrush range vegetation- Shown here was a population of low or dwarf sagebrush with reproduction (including seedling establishment and growth). No other plant species were present. Also clear in this photograph was surface of the stony soil of the zonal Brown great group. This soil superficially resembled the azonal Lithosol great group. This soil surface was similar to desert pavement described in this publication under the various deserts . Accelerated soil erosion might have a factor that was partly responsible for this soil surface condition. Such would be further evidence of range deterioration (for whatever reasons).
Low sagebrush range communities existing as edaphic climaxes are results of complex interactions and not just matters of shallow and/or infertile soil supporting sparse communities of dwarfish plants. Young et al. in Barbour and Major (1995, p. 780) summarized studies that found the low-permeability clay soils of low sagebrush "scab flats" resulted in perched water tables and conditions of inadequate soil seration in the plant root zone. Soil moisture regimes were suspected of being major features responsible for low sagebrush vegetation.
Burns District, Bureau of Land Management, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 406 (Low Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Low sagebrush/Idaho fescue association of Kagan et al. (2004). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
122. Dominant and associate- Dominant low sagebrush and associate slenderbush wild buckwheat growing together on a depleted range of the Artemisia arbuscula/Festuca idahoensis association.
High Lava Plains province of Franklin and Dyrness (1973, ps. 6, 32-34); Harney section (Big Sandy Desert) of Columbia Plateau physiographic province of Fenneman (1931, ps. 236, 272-273).
Burns District, Fureau of Land Management, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 406 (Low Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
123. Slender wild buckwheat (Eriogonum microthecum)- Slender buckwheat was the associate species on a degraded low sagebrush range. This is one of numerous Eriogonum species common in the Intermountain Region. The wild buckwheat species obviously have well-defined ecological niches as was shown in this series of sagebrush-dominated range types.
Burns District, Bureau of Land Manageament, Harney County, Oregon. June.
124. Depleted low sagebrush range- This range site in the transition between Owyhee Upland (primarily) and Basin and Range provinces in southeastern Oregon served as an example of the Artemisia arbuscula/Agropyron spicatum association of sagebrush steppe degraded to a seral stage in which no understorey of native herbaceous species remained. Sparse stands of cheatgrass (= downy brome) and widely spaced, stunted Russian thistle (Salsola kali var. tenuifolia= S. iberica) made up the herbaceous layer of this woefully degraded low sagebrush range.
This range had most likely deteriorated due to overgrazing as it most certainly had not been a farmed field, stage stop, oil field, frontier outpost, rail head, nuclear test site, church yard, school ground, or whore house. Franklin and Dyrness (1973, p. 241) cited earlier work by Tueller (1962) who reported that on low sagebrush-Idaho fescue association range overgrazing resulted in decreases in Idaho fescue, bluebunch wheatgrass, squirreltain bottlebrush and Junegrass while Sandberg bluegrass and several forb species increased as cover of low sagebrush remained constant. Young et al. in Barbour and Major (1995, p. 781) described overgrazed low sgebrush-dominated ranges as "stark communities with a great deal of bare ground between the show shrub canopies". They further observed that even cheatgrass invasions on low sagebrush range types were "low in comparison to A. tridentata sites". Been there; seen it. Now ya'll have too. Not a purty sight.
Owyhee Upland province (Franklin and Dyrness, ps. 6, 34-38 passim) that corresponded to Payette section (Owyhee Mountains) of the Columbia Plateau physiographic province (Fenneman, 1931, ps. 236, 244-248).
Vale District, Bureau of Land Management, Malheur County, Oregon. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 406 (Low Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Low sagebrush/bluebunch wheatgrass association of Kagan et al. (2004). Northern Basin and Range- Dissected High Lava Plateau Ecoregion (Thorson et al., 2003).
125. Low sagebrush-bluebunch wheatgrass- Now this was more like it: pristine Artemisia arbuscula/Agropyron spicatum association range. This range vegetation was an example of the other (of two) widespread Artemisia arbuscula associations described for eastern Oregon by Franklin and Dyrness (1973, p. 239). The climax range plant community speaks for itself.
Transition between Owyhee Upland (primarily) and Basin and Range provinces (Franklin and Dyrness, 1973, ps. 6, 34-38).
Vale District, Bureau of Land Management, Malheur County, Oregon. June. Estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 406 (Low Sagebrush). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). Low sagebrush/bluebunch wheatgrass association of Kagan et al. (2004). Northern Basin and Range- Dissected High Lava Plateau Ecoregion (Thorson et al., 2003).
126. Low or dwarf sagebrush (Artemisia arbuscula)- Low sagebrush is probably second to big sagebrush in dominance and designation of rangeland cover types in the sagebrush shrub-steppe. General appearance of low or dwarf sagebrush was shown in this example.
Vale District, Bureau of Land Management, Malheur County, Oregon. June.
127. Details of dwarf or low sagebrush (Artemisia arbuscula)- Specimen of low sagebrush with sexually reproductive leaders. Detail of leaders (shrub shoots) in second slide.
Vale District, Bureau of Land Management, Malheur County, Oregon. June.
Silver sagebrush-dominated range types- Another, though typically minor acreagewise, sagebrush species in the sagebrush steppe is silver sagebrush (Artemisia cana). Franklin and Dyrness (1973, p. 242) gave short shrift to silver sagebrush listing only the Artemisia cana-Muhlenbergia richardsonis association. Young et al. in Barbour and Major (1995, ps. 781, 784, 785) followed suit and listed the same association and an Artemisia cana-Sitanion hystrix comminity. These latter authors also specified that "Artemisia cana communities are characteristic of pluvial lakebeds in the uplands of the sagebrush steppe". The Society for Range Management rangeland cover type entry for silver sagebrush listed four habitat types based on subspecies of A. cana (Shiflet, 1994, p. 47).
Silver sagebrush-dominated range communities are similar in their abiotic habitat to low sagebrush-dominated vegetation described above. Both species are apparently edaphic climaxes whose soils become saturated by runoff and accumulations of spring melt water resulting in perched water tables (Young et al. in Barbour and Major, 1995, ps. 780-781). Local folks refer to these soil surface depressions with stands of Artemisia cana as "silver sagebrush sinks" or "silver sagebrush flats". Most commonly in this observer's experience these are consociations-- quite literally single-species communities (ie. populations)-- with no other vascular plants present.
128. Fenceline community contrast- A basin big sagebrush-green rabbitbrush association was on the left and a silver sagebrush sink on the right to provide perspective on habitat of silver sagebrush and physiognomy of the silver sagebrush rangeland cover type. Not the prominent depression in land (ground) surface between the two distinct sagebrush communities (= range cover types) on a "property line"-like demarcation.
There were a few "daring" green rabbitbrush amidst the "pure" stand of silver sagebrush, but otherwise this was a single-species stand (as such it could be argued that this was more of a silver sagebrush population than a silver sagebrush community). This phenomenon is, in this author's experience, the typical composition and structure of a silver sagebrush sink.
Burns District, Bureau of Land Managaement, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 408 (Other Sagebrush Types, Artemisia cana). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). One of the silver sagebrush playa associations of Kagan et al. (2004), but locally there was no herbaceous species to function as an associate. Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
129. Silver sagebrush flat or sink- This essentially "pure" stand of silver sagebrush developed on a depression in the High Lava Plains province (Franklin and Dyrness, 1973, p. 6, 32-34), Harney section (Big Sandy Desert)of the Columbia Plateau physiographic province (Fenneman, 1931, ps. 236, 272-273). Such ephemeral lakes pond runoff melt water from winter snow that results in a perched water that apparently only silver sagebrush could love. Big sagebrush (even the alluvial site-loving basin big sagebrush) is adapted to well-drained soils. Flooding kills subspecies of Artemisia tridentata (flooding is an effective sagebrush control method though one that is usually not an option). On range sites like the one shown here silver sagebrush faces no competition from its "big cousin" across the fence.
This example of silver sagebrush range vegetation was almost devoid of any other vascular plant species. While such examples are typical and suggested that the silver sagebrush sink type is shrubland or scrub and thus an island of the Great Basin Desert, this vegetation is part of the larger sagebrush shrub steppe (ie. grassland not arid shrubland or desert scrub). Communities of silver sagebrush in the heart of the semiarid shrub steppe could be interpreted quite properly as edaphic deserts, but they are not ecotones or ransitions between shrub-bunchgrass steppe and desert shrubland.
Burns District, Bureau of Land Management, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 408 (Other Sagebrush Types, Artemisia cana). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). One of the silver sagebrush playa associations of Kagan et al. (2004), but there was no herbaceous species for an associate in this example. Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
130. Silver sagebrush flat or sink- An interior veiw of the silver sagebrush stand presented in the two immediately preceding photographs showed spacing pattern (dispersion), structure, and composition typical of this range cover type. Characteristic cracking of soil sruface following ponding of snowmelt was distinct.
Burns District, Bureau of Land Management, Harney County, Oregon. June. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 408 (Other Sagebrush Types, Artemisia cana). Mixed Bunchgrass-Shrub Series of Brown et al. (1998). One of the silver sagebrush playa associations of Kagan et al. (2004), but there was not an herbaceous species present in this example to allow more specifics. Northern Basin and Range- High Lava Plains Ecoregion, 80g (Thorson et al., 2003).
131. Silver sagebrush (Artemisia cana)- Whole plant of silver sagebrush and detail of leaders (shoots) of this species. Burns District, Bureau of Land Management, Harney County, Oregon. June.
Separation of the big sagebrush form of Great Basin Desert (a cold, high elevation desert) from the sagebrush steppe (a semiarid bunchgrass-shrub savanna) is not a "ready made" distinction. The difference between aridity and semiaridity is often problematic even when some contrasts seem fairly obvious. When annual amount of precipitation is confounded by a routinely dry summer that resembles a "seasonal dought" and with porus soils and parent material of generally low water-holding capacity designating big sagebrush desert versus big sagebrush steppe can be a "tough call".
Transitions in vegetation are commonplace. Indeed, the savanna features of the sagebrush steppe are evidence that this immense range plant community is an ecotone between the Great Basin Desert (the sagebrush form thereof) and the Palouse Prairie. Along the periphery of the sagebrush steppe (especially in the Basin and Range province where steppe comes into contact with desert) there are further transitions (ie. transitions within transitions; ecotonal communities within a larger ecotonal community). One such area is between the Owyhee Upland and Basin and Range provinces. This is north of the Alvord Desert in the upper hills that receive somewhat greater precipitation (mostly snow) due to higher elevation and with some shelter afforded by basin-and-range topography.
An example of big sagebrush/mixed bunchgrass range vegetation in this transition land was shown below. The vegetation approached pristine and was likely of climax composition and structure. It seemed an appropriate way to end the chapter on sagebrush shrub-steppe and take up with the sagebrush desert of the Great Basin.
132. Desertlike sagebrush steppe- On land that was transitional between the Owyhee Upland (Owyhee Mountains of the Payette section of the Columbia Plateau province) and the northern Basin and Range province there are higher basins on which the sagebrush steppe has a physiognomy and structure that closely resembles big sagebrush scrub of the Great Basin Desert. These two views of a big sagebrush/mixed bunchgrass steppe were presented as examples of this transition vegetation which is itself within the transition zone, ecotone, of the sagebrush shrub steppe that is a savanna. The outward appearance of this range plant community resembled that of desert scrub. Big sagebrush desert scrub often lacks an herbaceous understorey or even herbaceous species other than as occasional plants. Features of this vegetation were intermediate between the more xeric big sagebrush steppe and big sagebrush desert scrub.
Native bunchgrass species that had considerable density and/or sizeable cover included bluebunch wheatgrass, squirreltail bottlebrush, Idaho fescue, Sandberg bluegrass, and Indian ricegrass (Oryzopsis hymnoides) in that approximate order without an obvious dominant species. Cheatgrass, a naturalized Eurasian annual, was also common locally, but it did not have the consistent distribution of the perennials.
Wyoming big sagebrush was the dominant shrub with both gray and green or Douglas rabbitbrush as the two associate woody species. The most common forb was tapertip hawksbeard.
Young et al. in Barbour and Major (1995, p.793) concluded that big sagebrush-bluebunch wheatgrass communities were so common and widely distributed that evidence of close ecological relations between these two species was conclusive.
Vale District, Bureau of Land Management, Malheur County, Oregon. June. Early estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). Variant of SRM 403 (Wyoming Big Sagebrush). Transition between Mixed Bunchgrass-Shrub Series and Sagebrush Series of Brown et al. (1998). Northern Basin and Range- Dissected High Lava Plateau Ecoregion (Thorson et al., 2003).
133. Details of big sagebrush/mixed bunchgrass range- In this closer-in view of the xeric big sagebrush-dominated steppe the general cespitose growth form of the native perennial festucoid grasses and the dispersion of these species was more apparent. Students should understand what is meant by growth form: "morphology of a plant, especially as it reflects physiological adaptation to the environment" (Allaby, 1998). The most abundant grass in this "photo-quadrant" was bluebunch wheatgrass, but squirreltail bottlebrush and Idaho fescue were also represented.
The higher elevation environment with its attendant cooler temperatures and greater precipitation created more mesic and generally less harsh habitats for range plants with the result being vegetation that was less desertic than that of lower elevations in the Basin and Range province. This land along a transition from uplands to lower landscapes had a complex of factors (each along its own gradient) that produced vegetation that was in transition from that which developed under sets of factors generally more favorable to sets of factors generally less favorable for plant life and development of vegetation.
The limited plant residue on the soil surface was also obvious. This is a characteristic feature of shrub-bunchgrass range. Soils of less or lower degrees of development are characteristic of certain forms of vegetation (eg. deserts) and topographic features (eg. steep slopes). Soils of big sagebrush are primarily of the Brown soils, a zonal great group of temperate to cool arid regions and having calcareous layers. These are not soils of deserts.
Vale District, Bureau of Land Management, Malheur County, Oregon. June. Early estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). Variant of SRM 403 (Wyoming Big Sagebrush). Transition between Mixed Bunchgrass-Shrub Series amd Sagebrush Series of Brown et al. (1998). Northern Basin and Range- Dissected High Lava Plateau Ecoregion (Thorson et al., 2003).
Organizational Note- Franklin and Dyrness (1973, p.212 ) distinguished among steppe, shrub-steppe, and meadow-steppe. Given the vast area covered and the floristic variation within the sagebrush shrub-steppe the above treatment was limited strictly to the shrub-steppe, the ecotonal transition or savanna between the bunchgrass steppe largely affilitated with the Palouse Prairie and the sgebrush scrub of the Great Basin Desert. Bunchgrass steppe that existed as "pockets" within the sagebrush shrub-steppe (steppe patches within the sagebrush shrub-steppe matrix in the vernacular of Landscape Ecology) was included under Palouse Prairie.
134. Upper limits or at the edge of the woodland zone- A mountain big sagebrush-bluebunch wheatgrass shrub steppe that developed on a predominately west slope in the Snake Range at the edge of the singleleaf pinyon pine-Utah juniper woodland. This and the next two slides were used to show the physiogonomy, structure, and species composition of a big sagebrush-bunchgrass steppe at it upper elevtional limits where it comes into cantact with the pinyon-juniper woodland.
In addition to the clear co-dominants of bluebunch wheatgrass and mountain big sagebrush other major (associate) species included needle-and-thread, Indian ricegrass (Oryzopsis hyennoides), and slender wheatgrass (Agropyron trachycaulum). Squirreltail and cheatgrass were occassionally present. Minor cover by cheatgrass indicated the high successional status (climax or near it) of this sample of hillside shrub steppe. Rubber rabbitbrush and viscid or Douglas rabbitbrush (Crysothamnus viscidflorus) were minor but indicator or diagnostic species of the sagebrush shrubland influence.
The oneleaf pinyon pine-Utah juniper woodland that contacted this sagebrush-bunchgrass savanna was shown in both the Pinyon-Juniper Woodland and Intermountain Forests chapters herein.
Great Basin National Park., White Pine County, Nevada. June, estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-50 (Wheatgrass-Needlegrass Shrubsteppe).SRM 402 (Mountain Big Sagebrush). Wheatgrss Series 142.21 Great Basin Shrub-Grassland 142.2 of Brown et al., 1998, p.40). Artemisia tridentata ssp. vaseyana / Psuedoroegneria spicata Shrubland (Nevada Natural Heritage Program, 26 September, 2003). [It is actually grassland not shrubland- editorial clarifiction by R.E. Rosiere as discussed below]. Central Basin and Range- Carbonate Woodland Zone Ecoregion, 13q (Bryce et al., 2003).
135. Mountain big sagebrush-bluebunch wheatgrass in the Great Basin- This image was of a "photo-transect" going uphill (foreground to background) that presented more detail of physiogonomy and structure of one of the more xeric forms of sagebrush shrub steppe.This Great Basin shrub-grass savanna was in the Snake Range and elevationally just below a oneleaf pinyon-Utah juniper woodland typical of that in the mountins of the Great Basin. (The pinyon-juniper woodland was covered in Intermountain Forests and Pinyon-Juniper Woodland chapters in this publication.)
A steep west slope with shallow soil was marginal for both of the co-dominants of this range cover type. The deeper rooted conifers rated the competitive edge on this range site, especially when combined with long-term fire exclusion/fire suppresion that was allowing unnatural invasion by Utah juniper and singleleaf pinyon pine. A bough of a small Utah juniper was barely visible in the left margin midground. Other important (associate) grass speciess included needle-and-thread, Indian ricegrass, and slender wheatgrass. Squirreltail and cheatgrass of downy brome were minor species. Sparcity of cheatgrass was consistent with the climax (or nearly so) state of this sagebrush shrub steppe range. Forbs were very limited.
Great Basin National Park., White Pine County, Nevada. June, estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-50 (Wheatgrass-Needlegrass Shrubsteppe).SRM 402 (Mountain Big Sagebrush). Wheatgrss Series 142.21 Great Basin Shrub-Grassland 142.2 of Brown et al., 1998, p.40). Artemisia tridentata ssp. vaseyana / Psuedoroegneria spicata Shrubland (Nevada Natural Heritage Program, 26 September, 2003). [It is actually grassland not shrubland- editorial clarifiction by R.E. Rosiere as discussed below.] Central Basin and Range- Carbonate Woodland Zone Ecoregion, 13q (Bryce et al., 2003).
136. Species composition of a bluebunch wheatgrass-mountain big sagebrush shrub steppe- Detail of the range vegetation displayed in the two immediately preceding photographs taken in foothills of the Snake Range. Bluebunch wheatgrass was co-dominant with mountain big sagebrush (though probably "first among equals" on basis of annual biomass production). Indian ricegrass, needle-and-thread, and slender wheatgrass were associate species with importance of each varying locally. Near absence of cheatgrass attested to the climax (or nearly so) composition of vegetation comprising this high-quality shrub steppe range.
Great Basin National Park., White Pine County, Nevada. June, estival aspect. FRES No. 29 (Sagebrush Shrubland Ecosystem). K-50 (Wheatgrass-Needlegrass Shrubsteppe).SRM 402 (Mountain Big Sagebrush). Wheatgrss Series 142.21 Great Basin Shrub-Grassland 142.2 of Brown et al., 1998, p.40). Artemisia tridentata ssp. vaseyana / Psuedoroegneria spicata Shrubland (Nevada Natural Heritage Program, 26 September, 2003). [It is actually grassland not shrubland- editorial clarification by R.E. Rosiere as discussed below.] Central Basin and Range- Carbonate Woodland Zone Ecoregion, 13q (Bryce et al., 2003).
CLARIFICATION: This author-photographer, to fulfill his duty as a range scientist, duly cited the various published units of vegetation that appeared to best describe the climax or high seral state range plant communities shown above. It was also deemed the duty of this writer to indicate, when necessary, errors made or biases held by those authorities when such mistakes or perspectives run counter to those of Range Science.
One such case was that presented above in treatment of big sagebrush-bluebunch wheatgrass steppe. This widespread, major unit of climax or potential natural vegetation takes on numerous forms depending on range site and distinctions more specific than those of range type or subtype (eg. subspecies of big sagebrush, slope and/or aspect of hillside). Notwithstanding, the unit has long been recognized as shrub steppe. Steppe? Get that. Steppe is a form of bunchgrass grassland. It is semiarid to arid grassland largely comprised of and dominated by cespitose grasses with a conspicuous cover of shrubs (big sagebrush in the example under discussion). This is a savanna or even grassland with scattered shrubs of big sagebrush (and other associated woody plants like rabbitbrush). It is not shrubland as Nevada Natural Heritage Program (26 September, 2003) labeled it.
This is not to say that there is no such shrubland (although that shrubland might not be potential natural vegetation). If climax vegetation is big sagebrush-bluebunch wheatgrass shrubland it is Great Basin desert and not Great Basin shrub steppe. Furthermore, the unit of big sagebrush-bluebunch wheatgrass vegetation listed by Nevada Natural Heritage Program (26 September, 2003) specified mountain big sagebrush (A. tridentata subspecies vaseyana). It is unlikely that vegetation with mountain big sagebrush as a dominant would be basin (= desert) vegetation.
What must be stated clearly-- in context of clarification-- is that it has been accepted by most range ecologist that the vast bulk of natural (= climax) bluebunch wheatgrass-big sagebrush vegetation is steppe (grassland) not shrubland. Nevada Natural Heritage Program (26 September, 2003) did not have a unit of natural vegetation of these two species (co-dominants) that it designated as grassland. In fact, this group of workers (Nevada Natural Heritage Program, 26 September, 2003) did not ever use the longstanding designation of grassland but opted for "herbaceous vegetation"--even though they had no prejudices against and repeatedly used the terms shrubland, woodland, and forest.
Likewise, other groups of the Natural Heritage Program, such as the Association for Biodiversity Information (April, 2001) in the SW Regional GAP Alliance Descriptions which included Nevada and Utah, did use the designation of grassland but only at levels above alliance (ie. there were no grassland alliances yet there were forest and shrubland alliances). Nevada Natrual Heritage Program (26 September, 2003) not only did use grassland as an alliance or association, it also did not show specific grasslands that do exist in Nevada. One example that was excluded was Indian ricegrass grasslands which were described by Tueller (1975, p. 25) and presented in the current publication in the chapter, Semidesert Grasslands, Great Basin. Again, the National Vegetation Classification for Nevada (Nevada Natural Heritage Program, 26 September, 2003) excluded (= omitted) bluebunch wheatgrass-big sagebrush steppe presented above which should have been Artemisia tridentata / Pseudoroegneria spicata Herbaceous Alliance (= Grassland).
In the expression of the author's students, "Go figure".
137. Spikes at sundown- Spike inflorescences of bluebunch wheatgrass (Agropyron spicatum). Some of the more disctinctive inflorescences of major dominant range grasses ascend to status of the sacred (or pert 'nar). The familar spikes of bluebunch wheatgrass is one of those. Crowns of the King of Sagebrush Steppe.
Tooele County, Utah. June, hard-dough grain stage.
138. Sagebrush at sundown- Leaders of mountain big sagebrush (Artemisia tridentata ssp. vaseyana) in late evening showing features of the subspecies of big sagebrush that is most common on mountain slopes. Aside from its ecological role in the sagebrush shrub steppe, big sagebrush is one of the shrubs so emblamatic of the Western Range that served an asethetic as well as an educational function-- especially when it followed bluebunch wheatgrass, the likely King of Sagebrush Steppe.
Tooele County, Utah. June, pre-bloom phenological stage.
The following four photographs taken along a catena in the eastern Great Basin portrayed a continuum of range vegetation extending from what were obviously shrub-steppe communities to open grasslands. With possible exception of the grassland vegetation these zonal range plant communities met commonly accepted and published standards of shrub steppe. These zones of herbaceous-shrubby vegetation, each a distinctive range plant community, also could be interpreted as forms of semidesert grassland. In fact, the "pure" grass form presented below was dominated by a festucoid grass species that is a climax dominant across much of the Great Plains. This reflects a floristic affinity between the Great Basin and Great Plains. Given this relatedness, in conjuction with physiogonomy and species composition of the "straight" grass (open grassland) form, this range community could almost qualify as mixed prairie.
These examples of Great Basin range vegetation were included in both the Shrub Steppe and Semidesert Grassland (Great Basin) chapters due to the continuum nature of some kinds of natural vegetation and in recognition of the unavoidable arbitrariness in typing certain range plant communities.
139. Great Basin landscape ("Believe It Or Not!")- Landscape-scale view of range vegetation on the eastern edge of the Great Basin. This "range-scape" was of an upland, a low hill and not a mountain range per se, about 25-30 miles west of the Colorado Plateaus physiographic province (map, Fenneman, 1935). The catena running from foreground to background (= ridgeline) extended from deep upland soils to an igneous rock outcrop and represented a transition from a generic deep upland range site to a breaks range site.
The range plant community on the igneous breaks was a Utah juniper (Juniperus osteosperma) woodland of smaller and apparently stunted trees. Below and contiguous with the coniferous woodland was a shrub steppe dominated jointly by rubber and Douglas or viscid rabbitbrush and Indian ricegrass (Oryzopsis hymenoides) and needle-and-thread (Stipa comata) with mountain big sagebrush and antelope bitterbrush (Purshia tridentata) as associates. Desert crested wheatgrass and cheatgrass or downy brome were present as two occasional, incidental, or minor members of this shrub steppe range vegetation. Downhill from this zone of shrub steppe vegetation there was another shrub steppe community co-dominated by mountain big sagebrush and Indian ricegrass with needle-and-thread, galleta (Hilaria jamesii), western wheatgrass (Agropyron smithii), and cheatgrass (in that approximate order of canopy cover). A fourth range plant community (foreground) was grassland or a shrub savann that varied from a consociation of western wheatgrass to a mountain big sagebrush-western wheatgrass steppe with an herbaceous mixture of Indian ricegrass, needle-and-thread, galleta, and downy brome "toped-off" with scattered individuals of rubber and viscid rabbitbrush.
These distinctive range plant communities were zones of climax vegetation determined primarily by edaphic and topographic features along with a pyric factor (shown below) in the same prevailing climate. These zonal range communities were shown and described separately in the next three photographs.
Juab County, Utah. June, estival aspect.
140. Two types atop a Great Basin hill- On this low hill in the eastern Great Basin Utah juniper formed a scrub woodland along the igneous rock outcrop of a breaks range site. Below the Utah juniper woodland on a site of more soil and slightly lower elevation was a shrub steppe with co-dominant shrubs rubber and viscid or Douglas rabbitbrush and co-dominant Indian ricegrass and needle-and-thread. Mountain big sagebrush and antelope bitterbrush were associate shrubs. Cheatgrass or downy brome was present in some otherwise bare spaces among clumps of the bunchgrasses. Desert crested wheatgrass occurred sparsely. These Eurasian grasses were minor members of climax range vegetation.
Large grass clumps in foreground were needle-and-thread, but despite such prominence Indian ricegrass was unquestionably the dominant herbaceous species (based on density, cover, and/or biomass).
Stark skeletons of dead Utah juniper bore charred wood from a wild fire that arrested (at least for a while) the downslope migration and invasion of this coniferous species into the shrub steppe. Zonation of vegetation was a function of edaphic, topographic, and pyric factors operating in concert. One of the major range management problems throughout the North American Intermountain West is steady encroachment of pinyon pine-juniper woodland onto climax shrub steppe range. This unnatural and terrible invasion apparently has been due largely to anthropogenically induced cessation (human suppression) of fire (much of it ignited by lightening). This manmade afforestation threatens valuable and fragile watersheds, critical wildlife habitat, and prized livestock ranges.
Junipers surviving among outcropping rock represent natural (climax) vegetation. These scrub trees avoided the fate of their downhill "dendred" (brother and sister trees) because on the harsh breaks range site there was not enough herbage to furnish fine, flammable fuels to carry a fire. Utah juniper does not resprout so these beautiful dead cedars will "stay dead". Periodic fire will be essential to maintenance of the shrub steppe (unless "Smokey's friends" decide to play with saws and axes instead of matches).
Juab County, Utah. June, early estival aspect. Juniper woodland was FRES No. 35 (Pinyon-Juniper Shrubland Ecosystem) and K-21 (Juniper-Pinyon Woodland), but emphasis here was on shrub steppe for which the closest designation was FRES No. 29 (Sagebrush Shrubland Ecosystem) and K-49 Sagebrush Steppe (yet rabbitbrush species were dominant shrubs). No SRM (Shiflet, 1994) for Rabbitbrush rangeland cover type. Mixed Bunchgrass-Shrub Series 142.22 of Great Basin Shrub-Grassland 142.2 (Brown et al., 1998, p. 40).Central Basin and Range- Sagebrush Basins and Slopes Ecoregion 13c (Woods et al., 2001).
141. When range vegetation plays by the rules- Textbook example of sagebrush shrub steppe: Indian ricegrass-mountain big sagebrush dominated rangeland with major associated grasses being needle-and-thread, western wheatgrass, galleta, and with cheatgrass a minor component species except where locally dominant on disturbed patches. Associated but widely scattered shrubs included rubber and Douglas or viscid rabitbrush and antelop bitterbrush.
Lower down on the sideslope, which and developed and functioned as a catena, western wheatgrass had displaced needle-and-thread as the main associate to Indian ricegrass and big sagebrush had replaced rabbitbrush as the dominant shrub.
All in one's perspective: this climax vegetation fits "perfectly" (at least "closely") with the ideal example of sagebrush shrub steppe. Conversely, this range plant community could be interpreted as semidesert grassland from perspectives of physiogonomy, obvious dominance by grass (cover and density), prevalence of herbaceous layers over woody plant cover, and greater biomass from grasses than shrubs. One potential basis for distinction between shrub steppe (a savanna by definition) and semidesert grassland is that of greater aridity or xericity of habitat with the latter being the driest of all major North American grasslands.
Absence of an Ephedra species from the grass-dominated Great Basin vegetation presented here in contrast to widespread occurrence of and, typically, dominance by E. nevadaensis on what are obviously semidesert grasslands (or closer thereabouts) elsewhere in the Great Basin suggested that the climax plant community above was shrub steppe not semidesert grassland. In such matters the individual reader-viewer will decide.
Juab County, Utah. June, early estival aspcet but most grasses progressing rapidly toward completion oa annual growth and dormancy. Most logical interpretation of this range vegetation in author's view was FRES No. 29 (Sagebrush Shrubland Ecosystem). K-49 (Sagebrush Steppe). SRM 402 (Mountain Big Sagebrush). Great Basin Shrub-Grassland 142.2- Ricegrass Series 142.23 (Brown et al., 1998, p. 40). Artemisia tridentata / Achnatherum hymenoides Shrubland (a plant association) (Nevada Natural Heritage Program, 26 September, 2003; there being no such classification for neighboring Utah). Central Basin and Range- Sagebrush Basins and Slopes Ecoregion 13c (Woods et al., 2001).
142. Sagebrush shrub steppe or semidesert grassland? (Or your guess as good as the next rangeman's.)- The lowestmost range plant community on the catena featured here was--depending on one's perspective and other biases--either a western wheatgrass-mountain big sagebrush steppe or a consociation of western wheatgrass having such a paucity of big sagebrush as to be a grassland. Indian ricegrass, needle-and-thread, and galleta were the other major (though only associate) grass species. Cheatgrass was "few and far between". Rabbitbrush species hardly qualified as associates to mountain big sagebrush.
On this catena-arrayed series of climax range communities western wheatgrass increased consistently until at lowest elevational zone western wheatgrass displaced Indian ricegrass as the dominant range plant. On the deeper, more mesic (or less xeric) edaphic environment the rhizomatous, colony forming habit of western wheatgrass had a decided competitive advantage over the strictly cespitose Indian ricegrass. With less bare soil available the prolific grain yields of Indian ricegrass was not the superior adaptation it is on more xeric habitats.
Juab County, Utah. June, early estival aspect but all grasses were speeding toward dormancy. The most rational perspective on this range vegetation in the author's judgment was FRES No. 29 (Sagebrush Shrubland Ecosystem). K-50 (Wheatgrass-Needlegrass Shrubsteppe). Not a close fitting rangeland cover type (Shiflet, 1994); Western Wheatgrass variant of SRM 402 (Mountain Big Sagebrush) or, descriptively but outside the Great Basin, Great Basin variant of SRM 607 (Wheatgrass-Needlegrass). Great BasinShrub-Grassland 142.2- Wheatgrass Series 142.21. Central Basin and Range- Sagebrush Basins and Slopes Ecoregion 13c (Woods et al., 2001).
143. What range vegetation is this?- These three photographs served as examples of Great Basin upland vegetation that was highly variable spatially and extremely species-rich (biologically diverse for any conservation biologist types who got lost and wandered onto a Range Management-based treatment) publication). Beyond that, what was it?
Start with a species list. Dominant grasses included (depending on loction) Indian ricegrass, needle-and-thread, galleta, threeawns of the Aristida purpurea complex, squirreltail bottlebrush, and sand dropseed (Sporobolus cryptandrus). Cheatgrass or downy brome was locally dominant in small, lower (deeper) microsites as where wind had created depressions in sand. Forbs were noticably limited consisting mostly of Eurasian crucifers especially tumble mustard (Sisymbrium altissimum) and pinnate tansy mustard (Descurainia pinnata). Major shrubs included Wyoming big sagebrush, rubber rabbitbrush, Douglas or viscid rabbitbrush, and Nevada jointfir. Less abundant and smaller shrubs included winterfat, spiny hopsage (Grayia spinosa), and spiny horsebrush (Tetradymia spinosa). Most individuals of the herbaceous species, including native perennials, had entered dormancy although this was only the fourth full day of summer.
The botanical diversity (plant species composition, structure, physiogonomy) coupled with lack of obvious dominant species and high proportion of robust perennial grasses indicated immediately that this was not degraded (at least not conspicuously so) range.
Soil varied from shallow to moderately deep sand. This range vegetation grew at elevations (an elevational or topographic zone) between valley (basin) bottom and mid-slope which was the zone of pinyon-juniper woodland which was visible in background in the first of these three slides. This corresponded to the Upper Sonoran (= Upper Austral) Life Zone of C. Hart Merriam.
In the view of the "old range school" of thought founded on Clementsian principles (OK, dogma in parlance of some Clements detractors) this range plant community could be regarded as a transition zone or ecotone between the regional sagebrush shrub steppe to the north and saltbush-shadscale salt desert to the south and west. Biodiverstiy of plant species and specific dominant plant species (eg. Wyoming big sagebrush, rabbitbrush, galleta) reflected influence of these regional climaxes as primary sources of certain species.
The range vegetation represented here was most logically interpreted as samples of one form of Great Basin-Colorado Plateau Sagebrush Semi-Desert described by West (in West, 1983, ps. 331-349; in Barbour and Billings, 1988, ps. 216-217). In this work West (in West, 1983, p. 331; in Barbour and Billings, 1988, ps. 216-217) emphasized clear distinctions between sagebrush steppe and sagebrush desert or semidesert, but he was less direct in describing variation with the Great Basin sagebrush desert/semidesert. The latter includes climax vegetation ranging from communities comprised almost exclusively of shrubs and often of one or two species (most notably Artemisia) to those consisting mostly of shrubs but those of numerous species to communities having a shrub canopy but with well-developed herbaceous layer(s). Those range communities existing primarily as shrublands (scrub) with little or no herbaceous understorey are more desert-like vegetation whereas those with herbaceous layers occupy the continuum closer toward sagebrush steppe.
Tueller (1975, ps. 4-6) distinguished a "northern desert shrub" in which "Artemisia is always one of the dominant species..." from the "salt desert shrub" in which dominant genera were typically Atriplex, Ceratoides, Sarcobatus, and Grayia. This was the classic division of the Great Basin Desert into the two major categories of 1) sagebrush and 2) saltbush/greasewood which was also followed in the cited works of West (eg. in Barbour and Billings, 1988, ps. 216-222). Tueller (1975) did not in his brief description of Nevada natural vegetation distinguish between sagebrush steppe and sagebrush desert or semidesert.
Range vegetation presented in this series of three photographs was clearly closer floristically and structurally to shrub steppe. Also of principal importance was the lack of dominance by Artemisia species and instead a 'sharing of the wealth" of this range environment with numerous woody as well as herbaceous species. For these reasons this range vegetation was included in the section devoted to the ecotone between sagebrush shrub steppe and the sagebrush form of Great Basin Desert. Not only is there a Great Basin-Colorado Plateau sagebrush shrubland and an Intermountain sagebrush steppe, but there is likely a transition zone between these with various forms of ecotones at different spatial scales. The range plant community shown here was most likely an example of such ecotonal vegetation.
Simply put, this rangeland vegetation was a mixed grass-mixed shrub ecotonal savannah, be it desert, semidesert, arid, xeric, etc.Given that savannahs are generally interpreted or defined as ecotones or transitions or vegetation the adjective of ecotonal could arguably be seen as redundant and eliminated.
Beaver County, Utah. Bureau of Land Management, Cedar City Field Office. June: estival aspect; approaching dormancy for major grass species. FRES No. 29 (Sagebrush Shrubland Ecosystem). No Kuchler unit at this mapping scale. Upland and sand variant of SRM 403 (Wyoming Big Sagebrush). A form of Mixed Bunchgrass-Shrub Series 142.22 within Great Basin Shrub-Grassland 142.2 (Brown et al., 1998, p.40). Central Basin and Range- Sagebrush Basins and Slopes Ecoregion 13c (Woods et al, 2001).
Mini-editorial: One (perhaps the) major weakness of long-used cover or, synonymously, dominance type method and also of the current National Vegetation Classification System promoted by prestiguous groups like the Ecological Scoeity of Ameria and The Nature Conservancy is that they are based on dominant species. Usually or traditionally this dominance has been based on the singular most dominant species or the one dominant woody and the one dominant herbaceous species. Hence, Society of American Foresters (Eyre, 1980) forest cover types and Society for Range Management (Shiflet, 1994) rangeland cover types were commonly named after the one dominant species (usually based on apparent cover dominance). For instance of the 24 published rangeland cover types for the Great Basin 15 were named and described in context of one species (Shiflet, 1994, ps. iv-v, 40-60). This form of designation/description goes back at least to the consociation concept of Frederick E. Clements which, of course, once again illustrates the Clementsian heritage in Forestry and Range Management. (Eat your hearts, Gleasonians!)
The National Vegetation Classification System, which traces back at least--at least in large part--to the Zurich-Montpellier School of Phytosociology of Josias Braun-Blanquet (eg. Plant Sociology, Braun-Blanquet, 1932), is even more extreme in reliance on dominant species. For example, in the National Vegetation Classifiction for Nevada (as of 2006 there was not one such scheme for Utah) there was an Artemisia tridentata / Achnatherum hymenoides Shrubland which covers the single most common, abundant, etc. grass species and one of the major shrub speceis in the rangeland vegetation presented immediately above. Yet, it was obvious (even using aspect dominance) that this range plant community could not be adequately defined, designated, described, or anything else using only those two species.
Frequently, climax vegetation (say, cover ot dominance types) is a consociation (of a single species) or an association (of two to three or four dominant species), but what about when vegetation does fit this pattern of composition? The example displayed here may not have been climax or potential natural vegetation, but given its remarkable biodiversity, species composition, and high absolute cover (and of climax herbaceous and woody species) by arid land standards it could not have departed too far from the state of climax. So what designation is to be used as the SRM (or SAF if trees had been present) dominance (= cover) type or the National Vegetation Classification association (or even alliance) level? There was none. Of the two systems, however, the cover type approach would be much more likely to be relevant. Among SRM Great Basin cover types (Shiflet, 1994, ps. iv-v) there were several that were named and described more generally and without reliance on one or a few dominants (eg. Riparian, Tall Forb, Alpine Rangeland, Salt Desert Shrub). Likewise, the Clements-based Biotic Communities scheme of Brown et al. (1998) had a designation both general and specific enough to apply to the example of range vegetation used here (recall from above). By contrast, the Ecological Society of America/The Nature Conservancy classification scheme was inappropriate (just not functional for describing cover or dominance types)
144. Rabbitbrush-basin wildrye steppe- On this relatively flat, bench (= behada) or similar topographic feture, a range plant community had developed that consisted of rubber rabbitbrush, viscid or Douglas ribbitbrush, and Great Basin wildrye. It appeared to be somewhat of a unique range plant community because this vegetation apparently was not described or recognized in the standard references. Successional status of this range vegetation was not known, but because a grazing- sensitive decreaser grass shared dominance with rabbitbrush this Great Basin plant community was presented.
This land was not prone to flooding, at least not with meaningful frequency. The rabbitbrush-basin wildrye range was nearly surrounded by the two natural plant communities of singleleaf pinyon pine-Utah juniper-big sagebrush-grass woodland that were designated as the Pinus monophylla / Juniperus ostersperma / Artenisia tridentata Woodland and Juniperus ostemsperma / Artemisia tridentata / Achnatherum hymenoides Woodland by the Nevada Natural Heritage Heritage Program (26 Septermber, 2003). Neither species of rabbitbrush or basin wildrye was common in the surrounding vegetation.
Nevada Natural Heritage Program (26 September, 2003) did not provide a unit of vegetation for the range plant community featured here. Nor did the Society for Range Management (Shiflet, 1994) recognize a Rabbitbrush rangeland cover type. Brown et al. (1998, p. 40) listed a Rabbitbrush Series 152.14 of Great Basin Desertscrub 152.1 (as distinct from Great Basin Shrub-Grassland 142.2), but such unit did not fit closely this range vegetation. Ericameria nauseosa Shrubland Alliance (Association for Biodiversity Information, April 2001), that included Nevada, was a title that appeared to apply somewht to this range vegetation. Ecological (including successional) treatment of the shrub-grass steppe traditionally has emphasized climax and seral plant communities as to dominance by numerous sagebrush species (eg. Arrtemesia tridentata, A. arbuscula, A. nova, A. cana). Readers were again referred to the classic summary works of Franklin and Dryness (1973, ps. 209-242 passim) and Young et al. (in Barbour and Major, 1995, ps. 763-796 passim). These authors did not indicate Chrysothamnnus-defined communities like those described for Artemisia, Atriplex, or Sarcobatus.
Most plant ecologists have not recognized a shrub steppe (or similar shrub-grass vegetation) or Great Basin desertscrub with Chrysothamnus nauseosus or C. viscidiflorus as a dominant. Clements (1920, p.157-158) was one of the few students of Great Basin vegetation to list separate consociations for both Chrysothamnus nauseosus and C. viscidflorus. Clements explained that when these two species are climax dominants in the Great Basin they "... are regularly found in mixtures, or as narrow band-like alternes". Clements (1920, p. 73-74) defined alernes as being caused by "interruptions of zonation" typically by disturbance or other successional factors. He explained further that alternes were frequent in climax areas wherever inequalities of surface structure occur.
It was not determined if the concept of alternating zonation as due to topographic features, for instance, explained this rabbitbrush-basin wildrye vegetation. (Zonation of woodland and forest vegetation in Great Basin mountains is common and readily recognized.)
This range had been subject to long-term cattle grazing up until a few years prior to photographpic recording of this Great Basin vegetation. What, if any, influence such grazing had on this range plant community was not known either. It seemed fairly certain, however, that use by cattle had not been induced severe disturbance or range depletion given that Great Basin wildrye was the dominant grass and there was cheatgrass was not a major component in the herbaceous layer. Furthermore, big sagebrush is not palatable to cattle so absence of the regional dominant could not logically be attributed to use of the range by cattle.
Fire was a more likely cause for presence of the two rabbitbrush species and absence of sagebrush because the former species are sprouters while sagebrush is a nonsprouter. Brown (1994, p. 149) observed that following fire on Great Basin desertscrub ecological role of nonspruting sagebrush "may eventually be taken" by sprouting shrubs including rbbitbrush. Plant succession in a Great Basin fire disclimax eventually goes from tropical or warm temperate climax speceies to cold temperate climax species (Brown, 1994, p. 149). This phenomena would not totally explain dominance by Chrysothamnus and absence of of Artemisia on the range presented here because species in both of these genera are cold temperate shrubs.
An ecological mystery remained. Would basin wildrye eventually come to dominate? Did it ever dominate?. Would periodic burning of this range during grass dormancy give basin wildrye a competitive advantage over sprouting shrubs which would lose some aboveground perennating tissue in fires? Was there previously another shrub besides rabbitbrush that was the woody dominant on this range. Nevada Natural Heritage Program (26 September, 2003) gave a unit (an association) of Artemisia tridentata ssp. vaseyana / Leymus cinereus Shrubland which--given bias of this group against grassland (described above)--could be interpreted as a basin wildrye-mountain big sagebrush steppe. If so, what became of the sagebrush.
Had a disturbance like fire taken out big sagebrush and permitted dominance by sprouting rabbitbrush? Or was this a narrow belt of natural rubber rabbitbrush-viscid rabbitbrush-basin wildrye steppe? Were the two rabbitbrush species ecological invaders? That is, were these two species that are commonly associated with big sagebrush to be regarded as noxious woody (= brush) range plants from a successional perspective (ie. was rabbitbrush seral to climax big sagebrush)? If so, would proper management be application of brush control practices? If the two rabbitbrush species took over the ecological role of big sagebrush as suggested by Brown (1994, p. 149) could rabbitbrush, that almost always co-exis with sagebrush species, be deemed as brush plants (ie. were rabbitbrush species invaders in regards to range condition class)? If so, was big sagebrush then also a brush species?
The answer to this last two questions was obviously, "Yes, but only when shrub cover is excessive by benchmarks of natural vegetation". These three species are native range plants. Their successional status is dependant on their relative proportions (cover, biomass, density, etc.) of the range vegetation as compared to the management goal (climax, high seral state, etc.) for that range, based on the specific range site(s).
Great Basin National Park, White Pine County, Nevada. June, early estival aspect. Units of designations for FRES, Kuchler, SRM rangeland cover type, biotic community, association, etc. were unknown. Central Basin and Range- Carbonate Woodland Zone Ecoregion, 13q (Bryce et al., 2003).
145. Interior of a shrub steppe of uncertain successional status- Rubber rabbitbrush-viscid rabbitbrush-basin wildrye shrub steppe in foothills of the Snake Range. Ecological status/role of the two shrub species was unknown. This range vegetation could be a degraded stand of basin wildrye for which chemical control of rabbitbrush is proper management for restoration of climax grassland. Alternatively this could be a climax Chrysothamnus spp.-Elymus cinereus shrub steppe. Or still yet, it could be a big sagebrush-Great Basin wildrye steppe in which rabbitbrush replaced sagebrush due to disturbance like fire (but probably not cattle grazing).
Great Basin National Park, White Pine County, Nevada. June, early estival aspect. Units or designations for FRES, Kuchler, SRM rangeland cover type, biotic communiy, association, etc. were unknown. Central Basin and Range- Carbonate Woodland Zone Ecoregion,13q (Bryce et al., 2003).
146. Happily co-habiting a habitat- Rubber rabbitbrush (larger shrub; left foreground) and viscid or Douglas rabbitbrush (smaller shrub, right foreground) surrounded by Great Basin wildrye (seven or eight grass clumps) that made up a shrub-grass steppe on a flat stretch of land in foothills of Snake Range. Successional status of this range vegetation was unknown.
Great Basin National Prak, White Pine County, Nevada. June, early estival aspect. Units or designations for FRES, Kuchler, SRM rangeland cover types, biotic community, association, etc. were unknown. Central Basin and Range- Carbonate Woodland Zone Ecoregion, 13q (Bryce et al., 2003).
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