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e ESPEY, HUSTON 3 ASSOCIATES, INC. 5.0 SAMPLE ADEQUACY Table K-16 summazizes the level of sampling achieved in productivity, vegetation cover and shrub density. Sample adequacy formulas and definitions of grassland and shrubland communities aze those reported in Wyoming Department of Environmental Quality Guideline No. 2, March 9, 1979, Revision 2. Shrublands aze defined as a vegetation type where shrub plus subshrub cover is more than 30 percent of the total vegetation cover (see Table R-17). By this definition both the mountain shrub reference and affected communities and the big sagebrush reference community aze shrub communities. The big sagebrush affected community (23 percent relative shrub cover) and the affected and reference meadow communities aze all by definition grassland communities. • A confidence interval of 10 percent or less of the mean was achieved with 90 percent probability for vegetation cover in all affected and reference azea communities. A confidence of 20 percent or less of the mean was achieved with 80 percent probability for shrub density in all affected and reference area communi- ties. Regazding productivity, a confidence interval less than 20 percent was achieved with 80 percent probability in all shrub communities (mountain shrub affected and reference and big sagebrush reference). A confidence interval of 10 percent of the mean was achieved with 90 percent confidence for the meadow reference community. The confidence interval for the meadow affected community was 12 percent of the mean at 90 percent probability and the confidence interval for big sagebrush is 11 percent of the mean at 90 percent probability. Cover data for herbaceous and shrub strata were taken on the same transects and consequently assumed to be one sample. The number of cover samples, the standazd deviation, and the sample adequacy require- went for vegetation cover are given in the 16 June 1980 submission . Table K-16, Sample Adequacy, page k-48, for each vegetation type. Sample adequacy for production data is also given in Table K-16. R-47