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- Species Diversity and Composition - <br />• The 1995 reclaimed area is dominated by native perennial cool season grasses and <br />native perennial forbs, comprising together slightly over 50 percent of total vegetation <br />cover (Figure 5). This is a larger proportion of total vegetation cover than is the case in <br />any of the Seneca II-W extended reference areas where in general nearly half of the <br />total vegetation cover is comprised of woody species (Figure 5). <br />The distribution of species density by lifeform (Figure 4) shows that the 1995 reclaimed <br />area is more similar to the reference areas than would appear to be the case from the <br />lifeform distribution of relative cover (Figure 5). This is important in that it shows that the <br />basic components of the original ecosystem have indeed been returned and that it is a <br />matter of relative proportions (Figure 5) that separates the reclaimed from the native <br />vegetation. Perhaps the largest difference with regard to species density is in the native <br />perennial forbs category, where native areas (at least the most extensive native types of <br />Mountain Brush and Sagebrush) tend to have half again more species (of native <br />perennial forbs) per 100 sq.m.. 2002 saw the addition of seven species of native <br />perennial forb to the list of occurrences in the 1995 reclaimed areas despite the dry <br />conditions. <br />Sample Adequacy <br />A summary of sample adequacy calculations for the parameters of cover, herbaceous <br />production, and woody plant density is presented in Table 13 (Appendix 1). As can be <br />seen in this table, the data sets for cover in the extended reference areas all achieved <br />sample adequacy. The 10 samples from the 1995 reclaimed area were two samples <br />short of meeting the adequacy standard. <br />Herbaceous production data sets were short of sample adequacy in all cases. In 2001 <br />the 15 production samples in each of the extended reference areas was sufficient to <br />achieve sample adequacy (ESCO 2002). However, the drought of 2002 accompanied <br />higher variability between clip plots leaving minimum adequate sample size estimated to <br />be from 29 to 70 plots (Table 13). <br />As usually is the case, the woody plant density data were sufficiently variable that the <br />• data set failed to meet sample adequacy by a wide margin. However, the approximation <br />