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L J I~ L J acre. They of course do not account for the shrubs present in high intensity special shrub planting areas. Species Diversity and Composition The 1995 and 1997 reclaimed areas are dominated by native perennial cool season grasses, comprising 40 to 50 percent of total vegetation cover (Figure 5). Native perennial forbs along with the two seeded introduced forbs, alfalfa and cicer milkvetch comprise 20 to 30 percent of the vegetation cover. The lingering annual/biennial component is primarily Pocilla biloba, an introduced species that comes out of the topsoil. It shows up in native areas in abundance only in certain springs, but apparently maintains a presence in the topsoil as ungerminated seed for at least several years. It apparently finds conditions in the maturing reclamation to its liking much longer than most introduced annual/biennial species. Were the sagebrush or mountain brush native areas suddenly to lose their dominant woody plant cover, it is strongly suspected that their lifeform composition would rapidly adjust to proportions similar to these of the maturing reclaimed lands. The distribution of species density by lifeform (Figure 4) shows that the reclaimed areas (especially the maturing 1995 and 1997 areas) are much more similar to the reference areas that would appear to be the case from the lifeform distribution of relative cover (Figure 5). What this shows is that the basic components of the original ecosystem are indeed returned and is a matter of relative proportions that separates the reclaimed from the native vegetation. Perhaps the largest difference with regard to species density is in the native perennial forbs category, where native areas tend to have somewhat more than twice the number of species (of native perennial forbs) per 100 sq.m.. The presence of introduced native perennial cool season grasses, while not an imminent threat to stand integrity, is a menacing potential problem. In particular, the presence of intermediate wheatgrass (Thinopyrum intermediumj and smooth brome (Bromopsis inermis), neither of which is planted is, as has been demonstrated on this site before, a long-term threat. It is suggested that each year, the particular lots of western wheatgrass and mountain brome (Ceratochloa marginata) a seller proposes to provide be sampled and submitted to a independent seed laboratory for determination of the presence of intermediate wheatgrass and smooth brome, respectively. If present, those 12