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production in 1996 than the alkali sagebrush reference area and 600% more production than the <br />big sagebrush reference area. As with both reference areas, perennial grasses were the <br />dominant lifefortn, averaging 51.89 g/m' (463 pounds per acre) or nearly 88 percent of the total <br />vegetation production (the alkali sagebrush averaged 99% and the big sagebrush reference area <br />averaged 83% relative cover). <br />Shrub Density: <br />Total shrub density on the reclaimed area averaged 1263.5 individuals per acre (3122.5 <br />stems per hectare). Big sagebrush had the greatest number of individuals per acre with <br />approximately 821, followed by woods rose with 317 per acre, douglas rabbitbrush with 90 per <br />acre, rubber rabbitbrush with 21 per acre, silver sagebrush with 10 per acre, and antelope <br />bitterbrush with 4 per acre. <br />Subshrubs were also included in the density study for informational purposes. Fringed <br />sagewort averaged 129 individuals per acre and common winterfat averaged 50 per acre. With <br />subshrubs included in the total individuals per acre, the total shrub and subshrub density on the <br />reclaimed area averaged 1443 per acre. <br />Table 7 in Appendix B summarizes Reclaimed area shrub and subshrub density and <br />provides statistical analyses for sampling. The top of page one of Table 7 summarizes sample <br />number, means, the shrub sample standard deviation, the number used for the one-tailed t test, <br />the d value, stems per acre, and the minimum sample number needed to meet sample adequacy <br />' requirements. Following this top section of page one is the actual sample data by species. <br />Shrubs and shrub totals are separated from subshrub data. <br />Sample Adequacy: <br />' Sample adequacy was obtained for all cover, production, and shrub density sampling <br />(Appendix A). The minimum number of samples required to meet Colorado Division of Minerals <br />' and Geology standards was calculated utilizing the following statistical equation: <br />where: <br />s' =sample variance (s=standard deviation) <br />~ =single tailed t-test (see Values of t for Given Probability Levels where <br />Degrees of Freedom is N-1 and Probability of a Larger Value is 0.1. <br />' d = 0.1 <br />x =sample mean <br />' 7 <br />