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x =sample mean Sample Variance for Sample Adequacy Calculations For one-stage sampling, variance was calculated as the square of the standard deviation (m). For the two-stage sampling of woody plant density, calculation of sample variance for use in the sample adequacy formulas was as follows (Expression 10.10 of Cochran 1977): 1-f, 1-f2 Vy = S,2 + S22 n mn . where: VY =Overall variance of woody plant density data f, = n/N= 15/20 =fraction of primary units sampled f2 = m/M= 3/607 =fraction of secondary units within each primary unit actually sampled S,2 =variance among primary unit means SZZ =variance among elements within primary units relative to the orimarv unit means • N =total number of primary units that exist within the sampling area and are potentially to be sampled n = number of primary units actually sampled M =total number of sample elements (secondary units) that exist within each primary unit and are potentially to be sampled m = number of secondary unit elements (2 m X 50 m sample transects) actually sampled within each primary untt Confidence Limits Confidence limits for comparisons to reference area based performance standards and technical standards were calculated using a 1-tailed t-value for alpha error probability of 0.10 at (n-1) degrees of freedom multiplied by the standard error of the mean of the sampled area. C.I. = t, s Jn Performance Standards COVER: A cover performance standard was calculated in accordance with procedures contained in the Seneca II permit and is based on twice the weighted average of herbaceous cover in the' Mountain Brush and Sagebrush reference area. An acreage weighted reference area • comparison based on the relative acreage of each predisturbance plant community was used. Weighting was based on Mountain Brush Reference area as 83 percent and Sagebrush