2015-04-29_PERMIT FILE - C1981008A (7)

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cheatgrass (Anisantha tectorum) had a cover of 6.8 percent (41 percent frequency). Blue grama 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 forbs was (2.6 and 0.2 g/m2, 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/50m2 or (12 stems/acre) and four -wing saltbrush with 0.2 stems/50m2 or (29 stems/acre). Nineteen species occurred in the cover samples, however, only 4 species had relative cover values of 1 percent or greater. Grasses (including annuals) comprised 6 of the species (see Table 2.04.10-21), while annual/biennial/perennial forbs totaled 4. Five shrubs occurred in the cover samples, as did two succulent and two trees. February 2015 JR -66) 2.04.10-69