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AppeMix A - Vegeta~/on Sampling for / 998 absolute cover on the reclaimed area is 96.1 percent of that sampled on the reference area (22.80 vs. 23.73 percent). PRODUCTION -1998 The sample mean for production values on the reclaimed area is more than double the sample mean for production values on the reference area (Tables A-8 and A-9). Determination of sample adequacy was based upon the "wet weights" of clipped vegetation in the field (Table A-2). Adequacy was reached on the reference area with fifteen samples. Production values on the reclaimed area were highly variable, and sample adequacy was not achieved after clipping fifty plots. Table A-2 Colorado Coal Mine No. 1 0.5 square-meter Production Plots Summary of Sample Adequacy Calculations Mean Computed Field "Wet" Weight Standard Actual Adequate Area (grams) Deviation Sample Size Sample Size Reclaimed Area 57.12 47.42 50 116.30 Reference Area 24.14 6.91 15 14.80 Density calculations were based upon the resulting total "dry" weights. The mean density on the ' reclaimed area is 542.52 lbs./acre, more than double the estimated production density of 238.13 lbs./acre sampled on the reference area. Since sample adequacy on the reclaimed area was not achieved, Equation 4 was used to prove that the lower confidence limit of the reclaimed area I production data is greater than the success standard (the reference area sample mean) at the 90% confidence level. The results of this analysis, shown on Table A-10, prove that the production I values on the reclaimed area exceed the 90% standard required in relation to the reference area data. SPECIES DIVERSITY -1998 Analysis of species present on the two areas indicates each is dominated by perennial grasses; 80.32 percent relative cover on the reference area, 87.28 (June) and 80.43 (Sept.) percent on the reclaimed area. Relative cover of perennial forbs is 6.38 percent on the reference area. Perennial forb relative cover on the reclaimed area for June and September are 5.24 and 5.29 percent, I respectively. Shrubs comprise 7.97 percent of the relative cover on the reference area with the reclaimed area having a relative shrub cover of 3.74 and 4.76 percent for June and September, respectively. Annua] forbs and grasses comprised 5.32 percent of the relative cover in the Band05J 1499-053.wpolFebruary 26. 1909 A-8