Laserfiche WebLink
4-106 <br />• cative of an overgrazed area. Western wheatgrass and Indian <br />ricegrass Urtyzopa~.e hymeno~de6 are minor graminoid components. <br />Forb cover is sparse, but relatively common forbs are: Russian- <br />thistle, burr-buttercup Cena.tocepha~a .t eh.t~.cu2a.ta, and tumble- <br />mustard b~.bymbn~.um aE.t.~ae~.mum. <br />Production <br />Estimated herbaceous production for the big sagebrush shrubland <br />ranges from 10.6 g/m2 to 104.1 g/m2 and averages 45.7 g/m2 or <br />407 pounds per acre. Cheatgrass accounts for 81 percent or <br />37.1 g/m2 of the total production. Total forb production is <br />low with an average of 6.2 g/m2, See Table 4,8-8. <br />• Density <br />Shrub density is high in this vegetation type (4,190 shrubs per <br />acre). Big sagebrush is the dominant shrub with 3,483 shrubs <br />per acre. Minor shrubs include; fourwing saltbush, rubber <br />rabbitbrush, mountain pepperweed Lep~.d.Lum mon~tanum, greasewood, <br />and broom snakeweed. Average height for all shrubs is 89 centi- <br />meters. Average shrub heights range from 26 centimeters for broom <br />snakewood to 118 centimeters for greasewood. See Table 4.8-9. <br />Diversity <br />Species richness is quite low in this vegetation type (index = <br />9.99). Equitability is also low (index = 0.62). This is related <br />to the strong co-dominance in this area by big sagebrush and <br />• cheatgrass. See Table 4.8-6. <br />