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• More importantly, the pathway of succession may be different due to drastic site changes (including substrate and soil stmcture) on mined lands and climatic patterns different from that which were present during establishment and development of these communities. Mountain brush vegetation types with tall shrub species represent well-established clonal communities that aze hundreds and perhaps thousands of years old (Dr. David Buckner, personal communication, 1992), Reproduction is almost exclusively by asexual means with little or no establishment from seed. Furthermore, the co- dominant tall shrub species, Gambel oak, occurs at the limit of its range extension and evidence suggests that it became established in a period with more different and wetter climatic conditions than now (Neilson and Wallstein, 1986). Reclaimed site conditions aze faz more xeric than native sites, probably even drier than the more xeric of the native sites, the sagebrush grassland type. Mesic conditions, in part sustained by the communities themselves, have played an important role in the establishment of the tall shrub communities. This, combined with other site conditions, has maintained their presence. The highly competitive and well established stands of vegetation (seeded or unseeded) established in reclaimed areas helps stabilize sites and return a functioning ecosystem. However, these stands also • slow the establishment of tall shrubs. Mcl,cnden and Redente (1990) found in studies on succession patterns in a disturbed sagebrush community, that after 12 years a disturbed sagebrush site initially dominated by grasses, continued to be dominated by grasses. Seneca II Mine observations of 15-yeaz- old reclaimed azeas adjacent to undisturbed native tall shrub stands indicate that little ox no extension of these well established shrub clonal communities has occurred in the reclaited azeas. Monitoring of revegetation at the neazby Seneca II Mine since 1985 shows initial reestablishment of shrubs may be favorable, but the density quickly drops off as the puennial herbaceous spedes establish. Tall shrub spedes are the most affected by the declines. The trend by 1993 shows somewhat of a leveling off in shrub density since the late 1980s. This is in spite of a large shrub and tree plant program and maximum use of duect haul topsoil. The composition of shrubs in reclaimed azeas tends to predominate with big sagebrush and snowberry. Any increase in reclaimed area shrub density usually comes from these two species. These to species also occur in native plant communities with a high composition of perennial herbaceous spedes. This, combined with site changes resulting from mining disturbance, may ultimately result in these two spedes being the dominant shrubs in the reclaimed plant communities and hence, one may antidpate a sagebrush grassland community dominating reclaimed landscapes many years from now. • The only effective means of stabilizing reclaimed sites quickly is to use seed mixes with a high composition of perennial grass speaes. On the other hand, to provide any opportunity for shrub PR-02 47 Revised 01/06