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overstory of Ponderosa pine and juniper. The concentration of shrub and tree species on lower slopes is an indication that soils are deeper here and moisture is more prevalent. There is essentially no vegetative cover on the ridge tops. The absence of vegetation is indicative of the shallow soils in this zone. Sandstone and shale outcrops are common along the ridge tops, especially on the large t barren ridge in the eastern portion of the permit area. The major limiting factor for vegetative production on this site is low available moisture. Annual precipitation rates are typically low and ' most precipitation occurs during the winter. Due to the shallow nature of the soil, the quantity of moisture held in recharge is low. Further, moisture is lost rapidly through evapo-transportation which is accelerated by the south and west orientation of slopes within the area. Trrieated Pasture A vegetation survey was performed in May, 1982 on the irrigated pasture ' between [he present mine area and the revision area to determine present productivity and cover. A total of 6 transects 150 feet long were samples as shown in Figure 2, Pasture Vegetation Survey. Five plots were taken along each transect at 30-foot intervals. Cover and ' productivity were examined at each plot. Cover was sampled using a 10-point frame one meter in length. Productivity was sampled by clipping vegetation within a 4 ft.z circular plot and segregating plant ' material into high and low palatability classes. This material was Cher, oven-dried and weighed. The plant species encountered during the survey are described in Table 11, Pasture Species List. ' The results of this survey are presented in Table 12, Pasture Vegetation Survey. The character of the vegetation changes significantly in different locations within the pasture. The major ' difference is apparently due to subtle changes in elevation that create wet and dry areas. Zone A in the northern portion of the pasture was significantly drier than other portions of the pasture. This resulted ' in a much lower cover and production than the other areas. Zone B generally was intermediate between t}~e wetter and drier zones. This area had much higher cover and production in the high palatability ' species than A and C. Zone C was a depression area that was obviously much wetter than the rest of the pasture. Juncus balticas (baltic rush) was the dominant vegetative cover here which is indicative of poor drainage. The high percentages of low palatability species such as Taraxacum officinales (dandelion), Cichorium spp. (chicory), and Convolvulis ' spp. (bindweed) is an indication of the poor management practices utilized on this pasture. SCS personnel reported that the owner has over-grazed this pasture in the past and continues to do so. 1 ' 27