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"in the cumulative presence data from 2m x 50m samples associated with the collection of a statistically <br />adequate sample of the reclaimed area and including alfalfa and /or cicer milkvetch, which have often been <br />included in seed mixes as nitrogen— fixers, due to the lack of suitable and available native nitrogen- fixers. <br />If the total cumulative number of native species in the reclamation sampling exceeds the average number of <br />native species per 100 sq.m. in the weighted average of the reference area sampling, then Test D is <br />passed. <br />Woody Plant Density Evaluation <br />The location of woody plant concentration areas in the BRB -1 were documented by field mapping and <br />assisted by aerial photography (Routt County DOQQ 2009) in the summer of 2010. During the mapping, <br />"High" density was reserved for those areas apparently (visually) greater than or equal to 2000 shrubs per <br />ac (one quarter shrub per sq.m.; 25 shrubs per 100 sq.m.). All other portions of the BRB -1 were labeled as <br />"Background" density. <br />Quantitative density data from fifty randomly located samples within the mapped woody plant concentration <br />areas were gathered from belt transects located and oriented randomly. In the Background woody plant <br />density portions of BRB -1, thirty sample points, in conjunction with cover and /or production, were located <br />and sampled for woody plant density. The belt transects (i.e. elongate sample plots) were 2 m x 50 m in <br />dimension and randomly oriented from the origin. Within each belt transect, all living trees and full shrubs <br />whose root crowns emerge within the plot boundaries were counted by species. Sample adequacy of the <br />collected woody plant density data from the BRB -1 was determined as follows: <br />( 2 <br />n min — (d x )2 <br />where: <br />n = the number of sample points needed in a given vegetation type to be capable of <br />detecting a 15% reduction in the mean with 90% confidence; <br />s = standard deviation (n -1); <br />t = the t statistic (one - tailed, 90% confidence; n -1 degrees of freedom; if n >30, t = 1.282 for <br />purposes of this study); <br />d = acceptable amount of inherent variability to be identified between the sample mean and <br />the true population mean (0.15 for purposes of this analysis); <br />12 <br />