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In 2012 and 2014, sample adequacy based on all -hit allowable herbaceous cover was not <br />achieved for the Mountain Brush type in the Extended Reference Area. Note however that <br />sample adequacy based on all hit total foliar cover was met in both 2012 and 2014 (Table C-4 in <br />Attachment D). An alternative that used the upper 90% probability value of the mean was <br />exercised. In other words, after having established a reliable estimate of population variance <br />having taken 21 samples in 2012 and 16 samples in 2014, the maximum possible values of the <br />mean (with 90% confidence) was taken to represent the allowable herbaceous cover of the <br />Mountain Brush type within the reference area. This was calculated in either of two ways below. <br />2012 data <br />1) Confidence Intervals <br />C.I. = (sNn)*t = (11.4/ 21)*1.325 = 3.28 <br />28.85 + 3.28 = 32.14 <br />2) Sample Adequacy Expression <br />Ss t.s <br />N = d2g2 <br />d = �((s2t)/(x2N)) = x((11.42* 1.3252)/(28.852* 16)) = 0.114 <br />X + d = 28.85 + (28.85 *0.114) = 32.14 <br />32.1% allowable herbaceous cover represents with 90% confidence the highest possible value of <br />the true mean for the Mountain Brush Reference Area in 2012. <br />2014 data <br />1) Confidence Intervals <br />C.I. = (sNn)*t = (21.42Nl6)*1.341 = 7.18 <br />40.68 +7.18 = 47.9 <br />SL -6 - 10 <br />