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2.3 Determination of Current Annual Production <br />In 2014 and 2015, along each randomly located transect, randomly located one-quarter square <br />meter quadrat (or larger) were clipped and bagged by lifeform. For each area evaluated, a minimum of <br />30 forage production transects were collected. From within each quadrat, all above ground current <br />annual vegetation within the vertical boundaries of the frame were clipped and bagged separately by life <br />form as follows: <br />Desirable Perennial Grass Desirable Perennial Forb <br />Annual Grass Annual Forb <br />Sub shrubs Noxious Weeds (if found) <br />All production samples were returned to the lab for drying and weighing. In 2014, air dry weights <br />were recorded and are presented in this report. In 2015, drying was conducted in an oven at 105° C <br />until a stable weight was achieved (24 hours). Samples were then weighed to the nearest 0.1 gram. <br />2.4 Sample Adeauagy Determination <br />Sampling within each unit (Reference Area or Phase III Bond Release Block) was conducted to a <br />minimum of 15 cover or 30 production samples. From these preliminary efforts, sample means and <br />standard deviations for total non -overlapping vegetation ground cover were calculated. The Cochran <br />formula (below) for determining sample adequacy was used to calculate nmin, whereby the population is <br />estimated to within 10% of the true mean (N) with 90% confidence. <br />When the inequality (nmin <_ n) is true, sampling is deemed adequate; and nmin is determined as <br />follows: <br />nmin = (t 2S 2) / (0.1X )2 <br />where: n = the number of actual samples collected (initial size = 15 or 30) <br />t = the value from the one -tailed t distribution for 90% confidence with n-1 <br />degrees of freedom; <br />S Z = the variance of the estimate as calculated from the initial samples; <br />z = the mean of the estimate as calculated from the initial samples. <br />If the initial samples do not provide a suitable estimate of the mean (i.e., the inequality is false), a <br />reverse null success evaluation which does not require adequacy would be employed (Rule 4.15.11 <br />(2)(c)). Sample adequacy results are presented on Table 1. <br />Page 9 <br />