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form are restricted by shallow depth to bedrock in this type. Slopes ranged 3 to 60 percent. Some areas mapped as such may occasionally receive supplemental moisture during the • growing season from adjacent agricultural activities, however, a sagebrush overstory with an associated understory of introduced and native species are present along with the irrigated pasture invader species Kentucky bluegrass. Total vegetation cover (first hit) for the type averaged 34 percent, with bare ground at 36 percent, litter at 22 percent, and bedrock or rock fragments at 8 percent (Table 2.04.10-21 ). Lichen and moss accounted for 1.1 percent of the mean cover. The shrub component dominated with 16.2 percent cover followed closely by the perennial grass component at 7.5 percent cover. Annual grasses at 6.8 percent cover, followed in importance. Consistent with the type designation, sagebrush (Artemisia tridentata) had the highest perennial species cover at 13.9 percent (47 percent frequency), while the ubiquitous invader of sagebrush rangelands, cheatgrass (Anisantha tectorum) had a cover of 6.8 percent (41 percent frequency). Blue grams had the third highest cover at 5.1 percent (29 percent frequency). The remaining species generally contributed less than one percent cover to the mean total vegetative cover. Total herbaceous production (including shrubs) totaled 43.01 g/m2 or 386.02 pounds/acre • (Table 2.04.10-22). Herbaceous production without the shrub component totaled 8.07g/m2 or 74.1 pounds/acre. The perennial shrub component contributed the highest value at 34.94 g/m (311.4 pounds/acre) followed by perennial grasses at 5.47 g/m2 (48.8 pounds/acre). While the contribution of annual grasses and fortis was (2.6 and 0.2 g/mz, respectively), their actual contribution to annual production is most likely higher, In order to sample the perennial species at the peak of their production, many of the earlier maturing annual species were senescent or were already gone from the stand. Woody plant density measurements in 1999 differed from 1987 as suffruticose species were not measured consistent with Guidelines for Compliance with Land Use and Vegetation Requirements for Coal Mining. Succulents were also not included in the density calculations. Mean density for the type was 17.23 stems/50m2 or 2,517 stems/acre (Table 2.04.10-23). Sagebrush dominated with an average density of 17 stems/50m2 or (2,483 stems/acre). Other species included Utah juniper with 0.03 stems/SOm2 or (12 stems/acre) and four-wing saltbrush with 0.2 stems/SOm2 or (29 stems/acre). . (REVISED 9/99) 2.04.10 - 71