2022-10-26_PERMIT FILE - C1981041

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• reterence area was contributed by native shrubs characteristic of the Colorado plateau and mesic to xeric areas. Species Composition In the sampling of the original greasewood reference area, eleven (l l) species were encountered during cover sampling. These included two perennial grasses (Distichlis spicata and a trace of Poa pratensis), one annual grass (Bromus tectorum), two perennial forbs (Cardaria drabs and Sueda fruticosa), three annual forbs (Descurainia Sophia, Lepidium perfoliatum, and Tragopogon dubius), and three woody plants (Chrysothamnus nauseosus, Sarcobatus vermiculatus, and Tamarix ramosissima). Sampling of the new greasewood reference area found four lifeforms with fifteen species (Table 1). The species included four perennial grasses, two annual grasses, two annual forbs, one succulent, and six woody shrubs. The new reference azea contains more total species, more perennial graminoids, succulents, and woody species. The original greasewood reference azea contained more annual and perennial forbs. The new reference area reflects a greater species richness with more varied lifeforms than the original reference area. CONCLUSIONS Sampling of the new greasewood reference area in 1999 for total vegetation cover, • herbaceous production, and species composition showed that the new reference area exhibited a greasewood shrub vegetation community representative of those typically found throughout the permit area of the Roadside and Cameo Mines. This azea will better represent the greasewood community for the purposes of revegetation success than the original greasewood reference azea, which exhibits a greasewood monoculture characteristic of a major riparian floodplain. A comparison of the two reference areas revealed compazable total vegetation cover with a wider variety of graminoids and woody plants comprising the cover in the new reference area Weedy forbs were more prevalent in the original reference area. Herbaceous production in the new reference area was nearly twice that of the original reference azea with the majority of herbaceous production comprised of annual and perennial graminoids. Woody plant density of the new reference area was 31 percent higher than the original reference area, however the overall structure of the new reference area is more open. This is explained by fewer large woody plants and a greater number of smaller shrubs. Fifteen species were represented in cover sampling in the new greasewood reference azea, whereas eleven species were encountered in the original greasewood reference area. Overall, the species encountered in the new greasewood reference area were indicative of a native community, with fewer numbers of weedy or invasive species. -9-