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1998 Reclamation are not much different than previous experience in the area, and the values in the 1993 and 1996 reclaimed areas, though somewhat greater, were still not particularly close to the 2000 stems/ac standard. Nonetheless, the species composition of these areas includes diveristy that can be considered important to the viability of these areas over the long-term. As the vegetation of the reclaimed areas responds to climate and management, among other environmental variables, it will be important that species representing principal components of the major vegetation types of the area (such as mountain brush) are present and available to become dominants again, should conditions support that development. Thus, perhaps more important than any overall woody plant density standard is the viable presence of primary species as potential centers of propagation and agents for future changes in species dominance. Species Diversity and Composition Species density data represent the total number of species present in randomly selected 100 square meter areas, each associated with a 50m cover sample transect. Species density data from the 2000 sampling are summarized in Table 17 and are graphically • presented in Figure 4. In 2000, total species density among all reclaimed and reference areas sampled ranged between 27.0 and 30.5 species/ 100 m2. The species densities observed in reclaimed areas were as high or hgiher than those is the reference areas. Of course, the additional opportunities for the presence of introduced annual and biennial forbs in these relatively young reclaimed areas accounted for some additional species. However, even in consideration of native species only, reclaimed areas, varying from 13.2 to 21.2 native species per 100 sq. m, compared favorably with reference areas which varied from 21.2 to 25.0 native species per 100 sq.m. Reclaimed areas tended to have more native perennial grass species and fewer native perennial forbs species than the reference areas. Apparent in Figure 4 is the general correspondence of lifeform distribution between the reference areas (right three columns) and the reclaimed areas (left three columns). The major difference is 1) the relatively greater abundance of introduced arinual and biennial forbs in the reclaimed areas (which declines with reclaimed area age) and 2) the relatively greater abundance of native perennial forbs in the reference areas. The latter difference has not shown a strong tendency to decrease with time over the period of observation. • 12