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-35- XII. Vegetation - Rules 2.04.10, 2.05.4(2)(e) and 4.15 Detailed vegetation information can be found on pages II.J-1 through II.J-24 of the application. The revegetation plan is provided on pages IV-1 through IV-15. The application identifies three vegetation types within the permit area that will be disturbed by mining. The affected vegetation types are aspen, mountain brush, and sagebrush-grass. The aspen type occurs on the mesic north and east-facing slopes, mountain shrub on south and west exposures, and sagebrush-grass primarily on the shallow soils on ridges and fine textured soils of alluvial fans. The applicant collected baseline data for herbaceous cover and production and woody plant density using a cluster sampling technique. Six to eleven cluster plots were randomly located within each vegetation type and from five to six cover and production samples were taken in each cluster. Herbaceous production was estimated by clipping m2 plots. Herbaceous cover was estimated by use of a 1/4 meter square plot divided into 100 square cells 2.5 cm on each side. Hundred meter square plots were used in estimations of woody plant density. The applicant has proposed to use sagebrush reference area No. l7 in revegetation success determinations due to the fact that with the reduction in woody plant density, the vegetation structure and potential herbaceous cover and production on reclaimed areas will most closely resemble the characteristics of the pre-mine sagebrush community. Herbaceous cover and production values were higher for the sagebrush community than for the other vegetation types sampled. Estimated herbaceous production was 98.7 g/mZ (880 lb/acre) and estimated herbaceous cover was 46.1% in the sagebrush reference area. In conformance with the landowner's request, the revegetation plan is directed primarily toward the establishment of ^rndurt~••o fnraga for livestock raa zinc. As such, the seed mix contains a number of introduced forage grasses such as timothy (Phleum ratense), crested wheatgrass (Agropyron cristatum) and red top (Agrostis alba Woody species will not be seeded or planted on reclaimed areas. On a seed weight basis, approximately 40% of the mix is introduced species. In the early years following revegetation, the introduced species will probably dominate the stand, and due to their relative ease of establishment and growth characteristics they will provide early soil stabilization. Over time, the more palatable species will probably decrease under grazing pressure, giving way to less palatable species included in the seed mix or derived from regenerative sources in live handled topsoil. Based on observations of previously reclaimed sites at Grassy Gap and other mines at similar elevations in northwest Colorado, live handling of topsoil will result in establishment of a number of native species, including shrubs such as big sagebrush (Artemisia tridentata) and snowberry (Symphoricarpos spp.).