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Total cumulative # of native species* _> avg. reference area native species density (# species / 100 sq.m.) <br />• * in the adequate sample of the reclaimed area and including alfalfa and / or titer milkvetch which have often been <br />included in seed mixes as nitrogen — fixers in light of the lack of suitable and available native nitrogen- fixers. <br />Comparing the cumulative number of species in what would often be twenty 100 sq.m. samples to <br />the average density in reference areas really compare a native species density per 2000 sq.m. in the <br />developing revegetated areas to the native species density per 100 sq.m. in the long established native <br />areas. As such it allows for a forward - looking assessment of the developing presence of native <br />species without necessitating the passage of the likely requisite several to many decades for them to <br />"fill-in" and actually achieve a density per random 100 sq.m. equal to that occurring in the <br />undisturbed areas. <br />SHRUB EVALUATION <br />Lands in the Seneca II Mine 2005 -2006 bond release testing in Bond Release Blocks BRB -1 and BRB -2 were all <br />disturbed prior to September 23, 1981. <br />The location of shrub patches in each of the three BRB sample areas was documented by field <br />mapping (preceded by mapping from stereo aerial photography) during Spring and Summer 2005. <br />During the mapping, "High" density was reserved for those areas apparently (visually) greater than or <br />equal to 1000 shrubs per ac (one quarter shrub per sq.m.; 25 shrubs per 100 sq.m.). All other <br />portions of the BRB were considered as "background" density. Exhibit 13 -13.3, Shrub <br />Concentration Areas, shows the locations of the areas selected. <br />In BRB -1 and BRB -2, the mapping of High shrub density areas will NOT be followed up with <br />separate quantitative sampling. Shrub density data associated with the cover sampling transects will <br />be collected, but no sampling centered on the High Density patches will be pursued in these areas. <br />Such cover samples as happened to have fallen in High Shrub Density patches of BRB -1 and BRB -2 <br />will be noted for descriptive purposes. <br />• In BRB -3, quantitative density data from mapped shrub patch areas was gathered from belt transects <br />located and oriented randomly within the individual shrub patches. Fifty (50) samples were located <br />in the "High" density patches. The number of samples per patch was proportionally based on the <br />size of the patch. In the Background shrub density portions of BRB -3, approximately twenty (20) <br />additional sample points (beyond the thirty (30) sampled in conjunction with cover and /or <br />production) were located and sampled for shrub density. The origin of the transect was placed in the <br />center of the patch, unless to do so prevented the belt transect sample area from staying within the <br />patch boundaries. If more than one sample point was located in a patch, they were evenly <br />(uniformly) spaced in the polygon. 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 <br />shrubs whose root crowns emerge within the plot boundaries were counted by species. Sample <br />adequacy of collected shrub density data from the BRB -3 shrub patch sampling will be determined as <br />follows: <br />( <br />nmin — ----------- <br />(dx)- <br />Where: <br />n—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 />ESCO Associates 13 -13 -10 7R40 * 03106 <br />