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As noted in prior vegetation monitoring (Savage and Savage, 1994, Savage and Savage, 1995), the 1985 Reclamation Area was initially seeded with a predominantly cool season mixture of reclamation grasses. Compared with the 1986 and 1987 Reclamation Areas, the 1985 Reclamation Area has always had a greater cool season graminoid component. CDMG has occasionally commented on this occurrence. Reviewing the relative cover of cool season graminoids within the 1985 Reclamation Area, from 1994 through 1996, a decreasing trend becomes very evident. Accounting for the prevailing precipitation regimes, eight of the ten cool season graminoids encountered between 1994 and 1996 on the 1985 Reclamation Area decreased significantly in relative cover. Four cool season grass species which had been represented in cover sampling previously, were not encountered at all during the 1996 sampling. Of the four dominant cool season graminoids (Agropyron cristatum, Agropyron dasystachyum, Bromus marginatus, and Bromus tectorum), al] showed significant decreases in relative cover overall from 1994 to 1996. Decreases occurred even after the wet spring and very successful 1995 growing season. The conclusion is that warm season graminoids, native fortis, and native shrubs are replacing the coo] season grasses in the 1985 Reclamation Area. This is illustrative of plant succession and diversification of the plant community. As the formerly dominant cool season grasses are replaced by warm season grasses, a temporary reduction in total vegetation cover may occur as the cool season grass niche space remains occupied by the senescing cool season grasses. The decrease in total vegetation cover may also be an artifact of sampling. The cool season grasses represented in the reclaimed areas • characteristically are large in stature with broad leaves and large clumps or dense sods. The individual plant species which has shown the largest increase in relative cover in all areas sampled is the diminutive Boute/oua gracilis. While becoming more dominant in the reclaimed vegetation communities, as indicated by increases in relative cover, the overall size and stature of the vegetation species within the community has been reduced. SPECIES COMPOSITION CDMG considers species composition of the revegetated and reclaimed areas to be an indicator of successful vegetation establishment. A standard has been set by CDMG for the evaluation of species composition at the Keenesburg Mine. To be judged successful, at final bond release, this standard requires that, "the species composition on the reclaimed area is such that there are at least seven perennial species of which four are warm season grasses and one is a forb. No one component of the above species should comprise greater than 40% relative importance nor less than 3% relative importance. Relative importance will be measured by calculating relative cover of the revegetation species. Vegetation species which may be used in the calculation of species composition may be any plant species not defined as a noxious or prohibited plant species, and may be native or introduced." . Species presence and numbers at all areas sampled in 1996 showed an increase from the initial sampling in 1994. The 1986 and 1987 Reclamation Areas showed equivalent or -13-