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3.0 RESULTS <br />3.1 Summary <br />Summaries of the success comparisons for the revegetation areas are provided on Tables i and 2 <br />and Charts 1 through 6. Tabular compilations of raw data and summaries for the aforementioned <br />sampling efforts are presented in Appendix A on Tables 3 through 30 and Charts 7 through 10. All <br />means presented in the following section are derived from statistically adequate samples, and there is at <br />least a 90 percent statistical confidence level associated with each reported mean. The areas included in <br />the Greasewood and Shadscale Comparison Areas passed all seven of the Phase III Bond Release success <br />comparisons in both 2011 and in 2012. A more detailed presentation of success standard comparisons is <br />presented in Section 4.0. <br />A total of 97 and 84 plant species were observed within all areas evaluated in 2011 and 2012, <br />respectively (Tables 3 and 4 in Appendix A). This consisted of 27 grass taxa, 47 forbs, 8 sub - shrubs, and <br />15 shrub species in 2011; and 21 grass taxa, 34 forbs, 7 sub - shrubs, and 22 shrub species in 2012. <br />Among these taxa is the occasional noxious or invasive weed such as musk thistle (Carduus nutans) or <br />cheatgrass, the latter existing in notable patches. It should be mentioned that musk thistle and field <br />bindweed (Convo /vu /us arvensis) were the only noxious weeds listed on the Guide line for the <br />Management of Noxious Weeds on Coal Mine Permit Areas (CDMLR, 1990) identified at Snowcap and <br />these weeds were primarily concentrated on the Shadscale Reference Area. There was only one <br />intercept on field bindweed on reclaimed areas in 2011 (Table 6). <br />3.2 Greasewood Comparison Reyeaetation Areas <br />In 2011, average ground cover of the Greasewood Comparison Revegetation Areas consisted of <br />69.3% live vegetation, 4.6% rock, 16.9% litter, and bare ground exposure of 9.2 %. Perennial cover <br />across the unit averaged 25.0% with annual and biennial cover averaging 44.3 %. Dominant taxa were <br />cheatgrass, greasewood (Sarcobatus vermiculatus), and annual wheatgrass (Eremopyrum triticeum) with <br />34.0 %, 10.4 %, and 8.9% average cover, respectively. Sub - dominant species included four -wing saltbush <br />(Atriplex canescens), forage kochia ( Kochia prostrata), and little barley (Critesion pusillum) with 6.8 %, <br />4.3 %, and 1.0% average cover, respectively. Total annual herbaceous production in the Greasewood <br />Comparison Areas totaled 872.1 pounds per acre with perennials contributing 182.0 pounds per acre. <br />Woody plant density averaged 1,943 shrubs per acre and was primarily comprised of greasewood, four - <br />wing saltbush, and shadscale (Atriplex confertifolia) (Table 10). Rubber rabbitbrush (Chrysothamnus <br />nauseosus) and Wyoming big sagebrush (Seriphedium tridentatum var. wyo) are also scattered <br />throughout the unit. This area had a total perennial cool- season grass relative cover of 1.2% and 11 <br />CEDAR CREEK ASSOCIATES, Inc. Page 16 Snowcap - Phase III Band Release <br />Evaluation - 2012 <br />