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standing dead, litter, bare soil, and rock were 0.4, 10.8, 6.0, and 0.5 percents, respectively. <br />• Species density in the Mountain Brush effected areas was 37.5 species per 100 sq. m., while <br />in the extended reference areas, it was 36.1 species per 100 sq. m. <br />Herbaceous biomass production averaged 785 pounds oven-dry per acre in the affected area <br />(Appendix 108, Table 10B-31 and 814 pounds oven-dry per acre in the extended reference area <br />iAppendix tOB, Table 10B-4). Similar to the understory of aspen areas, the herbaceous <br />biomass production of the mountain brush sites is limited by shading and other forms of <br />competition with the extensive woody cover, so even under favorable moisture conditions, <br />moderate herbaceous biomass production, as identified, would be expected. <br />Shrub density in the Mountain Brush vegetation type affected area averaged 14,804 stems per <br />acre (Appendix 108, Table tOB-51; slightly over half of this was mountain snowberry and most <br />of the remainder was attributable to Saskatoon serviceberry, black chokecherry, and Gambel's <br />oak. In the extended reference area, the average was 17,184 stems per acre (Appendix 108, <br />Table lOB-61, with a very similar proportional species composition. <br />Steep Mountain Brush Vegetation Type (Photos 17 through 241 <br />This vegetation unit is differentiated from the Mountain Brush unit by its occurrence on steeper <br />• sites with generally shallower soils and generally lower moisture availability. It is dominated by <br />native shrubs as is the Mountain Brush unit, but with less representation of black chokecherry <br />and more representation of big sagebrush. Native perennial cool season grasses (Appendix <br />10C, Table 10C-11 were much more abundant here than in. the Mountain Brush areas, and <br />comprised 16.5 percent of total vegetation cover. The major contributing species here were <br />western wheatgrass (Pascopvrum smithiil, Agassiz bluegrass, and bluebunch wheatgrass <br />IPseudoroecneria spicatal. Other common species included elk sedge, mountain brome, slender <br />wheatgrass, and Junegrass (KOeleria macranthal. Native perennial forbs accounted for a much <br />smaller portion of total vegetation cover than in the Mountain Brush type, with only 7.9 <br />percent of total vegetation cover. Although fifty-one species were observed, only western <br />yarrow, white-flowered peavine, and Canada goldenrod (So/idago canadensisl made substantial <br />cover contributions. Other common species included tapertip onion IA//ium acuminatum), <br />arrowleaf balsamroot (Balsamorhiza sagittetal, northern bedstraw lGalium septentrionalel, <br />tailcup lupine ILupinus caudaius/, microseris (Microseris nutansl, longleaf phlox (Ph/ox <br />lon.oifo/ial, lambstongue groundsel ISenecio intaerrimus), American vetch, and violet (Vio/a <br />praemorsal. Introduced annual grasses made up a minor portion (t.6 percent) of vegetation <br />cover. Species present included both cheatgrass (Anisantha tectorum/ and Japanese brome <br />(Bromus japonicusl. Common native annual and biennial forbs present included linearleai <br />collomia and bigfruit willowherb (Epi/obium brachVCarpum/. <br />I <br />LJ <br />55 Revised 9/98 <br />.... ,..,- ... . _.,_,_ a_ <br />_~ ..,,.,~.,, -KS ti.~-..M. -.,..,,, ._ <br />~.+.. .. s,~-t-.__:~:-:.i.., ~.u:,tcdiigffi*:..ig'c ~.ak~•.:'~Ye~4~.fi+'+,A.r.F :.9:.~ti::;•:,F~,,...:-~, ,.;~f:.::f.- dc5~e~r <br />... _.-.s - - - ~.. ~ :r.. <br />