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numbers rise. Sample sizes in Wadge Pasture sampling have been large enough over the years <br />• (usually 50) that observed means are thought to be fairly dependable. Assuming that the fifty <br />random points used in Wadge Pasture sampling in 2003 are a good representation of the <br />distribution of shrub growth, about ten percent of the area is likely to meet the existing shrub <br />standard of 900 stems /ac (1000 x 0.9). <br />In the PECOCO Pasture, the small sample size that has typically been used (10) is likely related <br />to the apparent fluctuations (chance sample placement "hitting" shrub patches some years and <br />not other years). <br />Species Diversity and Composition <br />Relative cover by lifeform (Table 24) is depicted for the various sampled areas in Figure 5. As <br />can be seen, the heavy dominance of woody species that characterizes the reference areas, <br />especially the Mountain Brush reference area is not matched in the reclaimed areas. In the older <br />sites at PECOCO and Wadge Pastures introduced perennial grasses (intermediate wheatgrass <br />and smooth brome) have asserted overwhelming dominance. Younger reclamation sites were <br />sown with native seed mixes and show more even balance between lifeforms. The uninvited <br />presence of introduced perennial grasses is unexplained. <br />• Species density reflects the total number of species present (richness) in 100 square meters one <br />meter to either side of the 50m cover sample transects. Species density data are summarized in <br />Table 23 and graphically presented in Figure 4. As can be seen there, a balanced presence of <br />species exists in the reclaimed areas that is not reflected in the relative cover data. The 1996 <br />and 1998-99 reclamation areas closely approached or exceeded the total species density of the <br />three reference areas. Were it not for the aggressive presence of the introduced perennial <br />grasses and fortis, it is likely that the species density in the PECOCO and Wadge pastures would <br />equal that of the reference areas. Of course, without those aggressive and productive species, <br />production would certainly be less. However, that parameter so greatly exceeds the standard set <br />by the reference areas that it would hardly matter from a bond release point of view. <br />Species density data observed since 1988 at the Seneca II Mine are compiled in the table below: <br />• 16 <br />