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Section 779.19 (b) Continued. Rule 4.15.7 Revised 12/3/80 duction estimates had been grazed. In contrast, when they sampled the reference area, they noted that almost none of the grasses had been grazed. The reference area is approximately a mile from water and on a more inaccessible site. It is believed that the dissimi- larity in production can be entirely attributed to the lack of grazing on the reference area. The only other statistical deficiency is in the sampling precision attained in the Treated Sagebrush Vegetation Type for shrub density and shrub intercept cover estimates on both the premine and re- ference areas (See Table 30, Summary of Statistical Analysis). In this case, the standard deviation tended to exceed the mean values, indicating, as would be expected, that there is a high variance within the sagebrush component in this vegetation type. Because of the high variance and small parameter means, sampling precision based on the adequacy formula (pg 779-60) is low. However, this is • consistent with the naturally high variance in shrub distribution on a treated shrub vegetation type. The statistical confidence for the shrub density parameter for the premine Alkali Sagebrush Vegetation Type was previously reported to be 79.8. A complete discussion of this apparent inadequacy is presented on revised page 779-60 aaa. In the Treated Sagebrush Vegetation Type the shrub density and intercept sampling adequacy was not achieved as can be seen at revised Table 30a, Summary of Statistical Analysis, and on revised page 779-60 aaa. However, the t test between the premine area and reference area indicates that there is not a statistically signifi- cant difference between the two areas. What the sampling data shows is that the treated sagebrush vegetation type has a high variance for the shrub component. The area was aerially sprayed with herbacide in 1964. As would be expected from this type of • 779-72 aaa