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overstory with an associated understory of introduced and native species are present along with <br />the irrigated pasture invader species Kentucky bluegrass. <br />• <br />Total vegetation cover (first hit) for the type averaged 34 percent, with bare ground at 36 percent, <br />litter at 22 percent, and bedrock or rock fragments at 8 percent (Table 2.04.10-21). Lichen and <br />moss accounted for 1.1 percent of the mean cover. The shrub component dominated with 16.2 <br />percent cover followed closely by the perennial grass component at 7.5 percent cover. Annual <br />grasses at 6.8 percent cover, followed in importance. Consistent with the type designation, <br />sagebrush (Artemisia tridentata) had the highest perennial species cover at 13.9 percent (47 <br />percent frequency), while the ubiquitous invader of sagebrush rangelands, cheatgrass Anisantha <br />tectorum) had a cover of 6.8 percent (41 percent frequency). Blue grams had the third highest <br />cover at 5.1 percent (29 percent frequency). The remaining species generally contributed less <br />than one percent cover to the mean total vegetative cover. <br />Total herbaceous production (including shrubs) totaled 43.01 g/m2 or 386.02 pounds/acre (Table <br />2.04.10-22). Herbaceous production without the shrub component totaled 8.07g1m2 or 74.1 <br />pounds(acre. The perennial shrub component contributed the highest value at 34.94 g/m (311.4 <br />pounds/acre) followed by perennial grasses at 5.47 g/m~ (48.8 pounds/acre). While the <br />• contribution of annual grasses and (orbs was (2.6 and 0.2 g/m2, respectively), their actual <br />contribution to annual production is most likely higher. In order to sample the perennial species at <br />the peak of their production, many of the earlier maturing annual species were senescent or were <br />already gone from the stand. <br />Woody plant density measurements in 1999 differed from 1987 as suffruticose species were not <br />measured consistent with Guidelines for Compliance with Land Use and Vegetation Requirements <br />for Coal Mining. Succulents were also not included in the density calculations. Mean density for <br />the type was 17.23 stems/50m2 or 2,517 stems/acre (Table 2.04.10-23). Sagebrush dominated <br />with an average density of 17 stems/50m2 or (2,483 stems/acre). Other species included Utah <br />juniper with 0.03 stems/50m2 or (12 stems/acre) and four-wing saltbrush with 0.2 stems/50m2 or <br />(29 stems/acre). <br />Nineteen species occurred in the cover samples, however, only 4 species had relative cover <br />values of 1 percent or greater. Grasses (including annuals) comprised 6 of the species (see <br />Table 2.04.10-21), while annual/biennial/perennial (orbs totaled 4. Five shrubs occurred in the <br />cover samples, as did two succulent and two trees. <br /> <br />(REVISED 8/15/00) 2.04.10 - 63 <br />