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Pasture sampling have been large enough over the years (usually 50) that observed means are <br />thought to be fairly dependable. <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 cover by woody species that characterizes the reference <br />areas, especially the Mountain Brush reference area, is not matched in the reclaimed areas. In <br />the older sites at PECOCO and Wadge Pastures, introduced perennial grasses (intermediate <br />wheatgrass and smooth brome) have asserted overwhelming dominance. Younger reclamation <br />sites were sown with native seed mixes and show more even balance between lifeforms. The <br />uninvited 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 from 2004 <br />sampling are summarized in Table 23 and graphically presented in Figure 4. As can be seen <br />r~ there, a balanced presence of species exists in the reclaimed areas that is not reflected in the <br />relative cover data. The 1997 and 2002 reclamation areas closely approached or exceeded the <br />total species density of two of the three reference areas. Were it not for the aggressive presence <br />of the introduced perennial grasses and fortis, it is likely that the species density in the PECOCO <br />and Wadge pastures would equal that of the reference areas. Of course, without those <br />aggressive and productive species, production would certainly be less. However, that parameter <br />so greatly exceeds the standard set by the reference areas That it would hardly matter from a <br />bond release point of view. <br />Species density data observed since 1988 at the Seneca II Mine are compiled in the table below: <br />15 <br />