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Sample Characteristics, Adequacy, and Comparability. Table 10-4, presented earlier, • <br />summarizes the means and standard deviations for cover, woody plant density, and <br />herbaceous productivity for the six vegetation types studied at the proposed mine site and <br />along the haul road corridor. Also presented in Table 10-4 are the results of <br />calculations used to evaluate sample adequacy (N ) and the comparability (t <br />min <br />calculations) between the affected and reference areas for the parameters measured. <br />Minimum sample size for woody plant density was met for all shrub communities, however it <br />was not met for the Aspen type within the mine site. In this case, per agreement with <br />CMLRD prior to the study, a maximum number of samples (n = 30) were taken. <br />Similarly, sample adequacy was not met in herbaceous production for the Aspen type (both <br />mine site and reference area), Mixed Brush at the mine site, and Meadow type in the haul <br />road. In the Aspen and Mixed Brush types, the maximum number of samples were collected. <br />The Meadow type (14,9 percent of the haul road) comprises a relatively small area and is <br />hi ghly variable due to varied topography and localized moisture regimes. <br />For the three vegetation types in the mine site (Aspen, Mixed Brush, and Sagebrush), • <br />herbaceous production was collected during 1983. The 1983 production was consistently <br />higher in these types than that found during earlier studies (ERT, 1979). The increases <br />ranged from about 50 percent in the Aspen type to as much as 500 percent in the Sagebrush <br />mine site and reference areas. Note that the precipitation from August 1982 to July 1983 <br />was about 20 percent above the long-term average. It seems likely that this increased <br />precipitation was at least partially responsible for the higher production measured during <br />this study. <br />References <br /> <br />Bonham, C.D., L. Larson, and A. Morrison. 1980. A survey of techniques for measurement <br />of herbarceous and shrub production, cover and diversity on Coal Conditions in the <br />West. (Draft) Office of Surface Mining, Region V, Contract J7090435. 81 p. <br />Craighead, J.J., F. C. Craighead, R.J. Davis. 1963. A Fieldguide to Rocky Mountain <br />Wildflowers. Houghton Mifflin Company. (Boston, Mass.) <br />J <br />40 <br />