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Woody plant density in the reclaimed areas monitored in 2001 was either very low (57 stems per acre in the 1994 and 1999 reclaimed areas) or gratifyingly high {1093 and 996 stems per acre in the 1997 general reclamation and 1997 Shrub Establishment areas, respectively). Species Diversity and Composition Relative cover by lifeform (Table 26) is depicted for the various sampled areas in Figure 5. As can be seen the heavy dominance of woody species that characterizes the reference areas, especially the Mountain Brush reference area is not matched in the reclaimed areas. In the oldest ungrazed reclamation sampled (1994), the abundance of the introduced perennial forb alfalfa is very large (over half of the vegetation cover). Younger reclamation sites show more even balance between lifeforms. Older but grazed reclamation (PECOCO Pasture and Wadge Pasture) show control of introduced perennial forbs, but introduced perennial grasses (intermediate wheatgrass and smooth brome) have asserted overwhelming dominance. Species density reflects the total number of species present (richness) in 100 square meters one meter to either side of the 50m cover sample transects. Species density data are summarized in Table 25 and graphically presented in Figure 4. As can be seen there, a balanced presence of species exists in the reclaimed areas that is not reflected in the relative cover data. But for the • aggressive presence of the introduced perennial grasses and forbs, it is likely that the species density in the PECOCO and Wadge pastures would equal that of the reference areas. Of course, without those aggressive and productive species, production would certainly be less. However, that parameter so greatly exceeds the standard set by the reference areas that it would hardly matter from a bond release point of view. Species density data observed since 1990 at the Seneca II Mine are compiled in the table below. Reclaimetl Areas Mountain Brush Ref. Sagebrush Ref. Alkali Sgbr Ref. 2001 15.9 - 26.8 22.7 23.2 22.7 2000 6.3 - 12.5 30.3 25.9 - 1999 25.8 - 27.5 36.2 32.8 -- 1998 10.4 - 15.2 29.6 25.1 - 1997 15.5 33.9 36.4 - 1996 13.5 - 19.7 27.2 35.4 - 1995 10 - 18.0 40.4 37.3 - 1994 15.7 - 19.9 31.3 28.3 - 1993 11.6 - 20.0 28.6 29 - 1992 12.1 - 19.0 28.7 24,6 - 1991 9.9 - 18.3 22.9 27.7 - 1990 9.5 - 18.9 22.9 25.9 - Species density of the reclaimed areas has always been observed at levels below the reference • areas. To a large degree this relates to the smaller presence of native perennial forbs in the 17