2008-12-22_REPORT - C1980001 (3)

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2006 Edna Mine Vegetation Sampling Report Table 2-1). The replacement reference area was also equivalent in herbaceous production to the western half of the original reference area and the whole reference area (Table 2-2). Herbaceous production did differ between the pre-mowed portion in 2005 and the replacement section, but the same was true in the western (un-mowed) portion and the whole area, suggesting that other factors, such as climate, are likely affecting this result. Using mean herbaceous cover and herbaceous production values from the new snowberry sage reference area (comprised of the un-mowed western portion of the original area and the new replacement area) along with the oak mountain shrub reference area; weighted mean values were calculated from the following equation: Xw=(.83*Xss)+(.17*Xom) Xw = weighted mean Xss = herbaceous cover or production mean of snowberry sage reference area xom = herbaceous cover or production mean of oak mountain shrub reference area The weighed mean of the herbaceous cover standard was calculated to be 24.1% (83% of 24.1 + 17% of 23.7). The herbaceous production standard was calculated to be 41.6 g/m2 (83% of 36.9 + 17% of 64.8). The West Ridge Topsoiled BRU and Moffat Topsoiled BRU vegetation parameters were compared to the reference areas' weighed means to evaluate vegetation performance on the reclaimed lands. It should be noted that a weighed mean was also calculated using only the western (un-mowed portion) of the snowberry sage reference area along with the oak mountain shrub area. There was not a sufficient sample size in the western portion alone to meet sample adequacy standards; however, both herbaceous cover and production were higher in the western portion than in the whole. In this case, the weighted mean of the herbaceous cover was calculated to be 27.6% (83% of 28.3 + 17% of 24.2) and herbaceous production was calculated to be 43.9 g/m2 (83% of 39.6 + 17% of 64.8). Using these higher standards the West Ridge Topsoiled BRU and Moffat Topsoiled BRU areas still met or exceeded the cover and production standards. These numbers are not included in the supporting documents, but can be provided if necessary by request. 2.1. Supporting Documentation Tables 2-1 and 2-2 summarize results of t-tests performed to determine equivalence of herbaceous cover in the snowberry sage replacement reference area. Tables 2-3 through 2-6 summarize vegetation data and statistical tests for the oak mountain shrub reference area. Tables 2-7 through 2-10 summarize vegetation data and statistical tests for the snowberry sage reference area. Tables 2-11 and 2-12 provide a list of the community plant species sampled at the respective reference areas. Figures 2-1 and 2-2 are site photographs, and Figures 2-3 and 2-4 display transect location maps for the reference areas. Habitat Management, Inc. 4 October 19, 2006