2008-09-29_PERMIT FILE - C1981019A (33)

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RULE 2 PERMITS Juniper Community Within the permit area the juniper community is limited to the area around Mount Streeter and the bluffs along the lower portion of Taylor Creek and Goodspring Creek. The community is dominated by an open overstory of Utah juniper (Juniperus utahensis), rarely over 15 feet tall, with big sagebrush as a major associate. The open understory contains a sparse population of grasses and forbs with the major species being Indian ricegrass (Oryzopsis hymenoides), bluebunch wheatgrass (Agropyron spicatum), prickly pear cactus (Opuntia polycantha), and lupine. According to the 1975 USDI, BLM, EMRIA Taylor Creek Study, the herbaceous cover for the juniper community was determined to be 1.6 percent. Overall, the productivity of the juniper community is low due to the combined effects of shallow to rocky soils, southerly aspect and steep, highly erodible slopes. Productivity, as determined by the BLM is .036 AUM's per acre for the juniper type in this area. Only a limited amount of this vegetation community was disturbed mainly for material to be crushed for pit haul road use during the initial permit term. Ashen Woodland Communi The aspen community is very limited within the permit area comprising less than to of the area to be mined. Groves of aspen occur within the upper reaches of Streeter and Taylor Creek watersheds in locations where snow melt continues to provide moisture later in the spring. The aspen community is characterized by tall, dense groves of aspen (Populus tremuloides), as the primary upper level overstory with elements of the mountain shrub community, particularly serviceberry and chokecherry, as a secondary overstory. The deep loamy soils combined with the favorable soil moisture condition continuing on into summer contribute to a rich, diverse and productive understory. Grasses and fortis are very prevalent with the dominates being Kentucky bluegrass, mountain brome, yarrow, prairie coneflowers, and American vetch. According to 1988 sampling herbaceous cover was determine to be 73.00%. For additional details refer to Table 2.04.10-3, 1988 Herbaceous cover by species. Production sampling indicated 772 lbs/acre of herbaceous production. According to these production figures, the carrying capacity in AUM's, assuming 1000 pounds of air dry forage per AUM at 50% utilization, would be .39 AUM's per acre. Productivity, as determined by the BIM, is .25 AUM's per acre for the aspen type in this area indicating that the condition of the mountain shrub community within the permit area is good. As previously stated, the deep, loamy soils and high soil moisture conditions together with the generally northern aspect combine to provide the required conditions for the aspen community. Where soil moisture becomes less plant available earlier into the summer, elements of the mountain shrub community begin to dominate. Generally, this occurs due to a change in aspect of the topography or shallower soil depth. Rule 2 Permits 2.04.10-4 Revision Date: 6/23/08 Revision No.: MR-91