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2.4 Determination of Woody Plant Density <br />Belt transects were co- located with the ground cover transects to obtain a reasonable estimate of <br />the woody plant density of the mine site. At sample sites #2 and #3, a 4 meter by 25 meter long belt <br />transect was established in the direction of the next sampling point (typically in a cardinal compass <br />direction). Then within each belt, all woody plants (shrubs, trees, sub - shrubs, and succulents) were <br />enumerated by species. Determination of whether or not a plant could be counted was dependent upon <br />the location of its main stem or root collar where it exited the ground surface with regard to belt limits. <br />Sample adequacy was determined for informational purposes only. On sampling site #1 and #4, total <br />counts of live shrubs were conducted instead of sampling. This required systematically walking the entire <br />unit and recording every live shrub within that unit. <br />2.5 Sample Adequacy Determination <br />Sampling of the individual units was restricted to 10 samples for cover, production, and woody plant <br />density due to the managerial nature of collected data (20 for cover and 30 for production on reference <br />areas). However, for informational purposes, sampling adequacy (nmin) has been calculated for each <br />variable in each sampling unit in accordance with the Cochran formula (below) for determining sample <br />adequacy, whereby the population is estimated to within 10% of the true mean (p) with 90% confidence. <br />follows: <br />When the inequality (n <_ n) is true, sampling is deemed adequate; and n min is determined as <br />Where: n = the number of actual samples collected with a minimum of 10 in each unit; <br />t = the value from the one - tailed t distribution for 90% confidence with n -1 degrees of <br />freedom; <br />s 2 = the variance of the estimate as calculated from the initial samples; <br />x = the mean of the estimate as calculated from the initial samples. <br />CEDAR CREEK ASSOCIATES, Inc. <br />nmin = (t / (0.1 x )2 <br />Page 12 Snowcap - Revegetation Evaluation - 2011 <br />Monitoring <br />