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Introduced annual and biennial (orbs and introduced perennial forbs each produced less than <br />• 0.5% of total vegetation cover. In the former, twolobe speedwell accounted for 100% of the <br />lifeform cover total and in the latter, Canada thistle provided 100% of the lifeform cover total. <br />Also present were several native annual and biennial forbs and one succulent. <br />Total vegetation cover for the Sagebrush reference area in 2002 was,46.7%. Standing dead, <br />letter, bare soil, and rock comprised 9.4%, 34.5%, 9.3% and 0.10% cover in 2002. Species <br />density averaged 24.2 species/100sq.m. <br />Production <br />(Table 19) <br />Herbaceous production averaged 805 Ibs/acre. Alfalfa was not present. <br />DISCUSSION <br />Climatic Conditions <br />Of the twelve months between the July 2001 and the July 2002 sampling, ten were below <br />average in precipitation at the Seneca II Mine (Figures 6a and 6b). In particular, during the period <br />of October 2001 through July 2002, every month had below average precipitation (Figure 6b). <br />• When compared to other years that monitoring has occurred since 1987, the cumulative 12 <br />months previous precipitation total ranked 2002 well below the other years in that period (Figures <br />7a and 7b). Similarly for the cumulative 6 month comparison (Figures 8a and 8b) and the <br />cumulative 4 month comparison (Figures 9a and 9b): the 2002 ranks as the driest of the 15-year <br />record. With regard to temperature, cumulative January through July 2002 warmth was 2 to 3 <br />percent below average meaning that extra warmth probably did not exaggerate the low <br />precipitation situation. <br />Cover <br />Calculation of 90 percent of the cover performance standard appropriate for 2002 sampling is <br />demonstrated below. <br />Mountain Brush Reference Area herbaceous cover x 2 = 15.7 x 2 = 31.4 <br />Sagebrush Reference Area herbaceous cover x 2 = 21.4 x 2 = 42.8 <br />90 percent of the Cover Standard = 0.90 [0.83(31.4) + 0.17(42.8)] = 30.0% <br />As can be seen in Figure 1, the allowable herbaceous cover of all reclaimed areas except the <br />1998 reclaimed area falls above the standard set by the Mountain Brush and Sagebrush <br />• reference areas. <br />15 <br />