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Section 779.19(b) Continued. Rule 4.15.' Revised 12630/80_ application, the treatment did not equally affect the entire area; consequently, the resulting community is artificial, i.e., the shrub component in the evmlving community is not normally distributed nor comparable to the shrub component of adjacent, untreated plant communities. It is contended that the present sampling is representative of the shrub density and inte=cept cover. Further random sampling in this vegetation type would probably continue to show a high variance. The combined sample size for the premine and reference area is 36 transects of five m2 plots each or a total of 180 m2 plots each or a total of 180 m2 plots which were read over a total of 1,800 transect meters (1.~2 miles). Since the t test was highly non-significant and the parameter means are higher for the reference area, it is proposed that the reference area be deemed acceptable as a measure of the shrub component on the Treated Sage- brush Vegetation Type. In order to further demonstrate that the shrub component in the Treated Sagebrush Vegetation Type is not normally distributed, a graphical analysis of the shrub density . data £or the premine area was prepared. The results of this analysis is present in Figure 38 the percent frequency of shrub density. This method of il?ustrating plant distribution based on field data is widegy used. Harold F. Heady (in "A comparison of the chartnng, line intercept, and line point methods of sampling shrub types of vegetation", Journal of Range Management 12_180-188, 1959) recorded distribution curves for low density shrub species which were identical to that of the shrub com- ponent in the Treated Sagebrush Vegetation Type and stated that the low density shrub species did not approach a normal distribution. He also found that another affect of non-normalcy vas to produces high variability in the variance from one sample to another. This resulted in a greater ratio of the standard deviation to t8ne mean causing a high sample size requirement. Dr. Heady also concluded that "the number of plots needed to sample the species of lesser importance may be so great that the sampling is beyond the facilities of the invesRigation; and that the seriousness of non-normalcy is nod great because sample means from such populations are normally distributed about the population mean ..." This is re- flected in the use of transect means in the statistical analysis. These findings confirm the statistical and 779-72 bbbbb: