2021-12-22_PERMIT FILE - C1981019A

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RULE 2 PERMITS Mean density of woody species in the aspen study area samples was 31.0 shrubs per 50 square meters and 7.5 aspen trees per 100 square meters. Dominant shrubs included western snowberry with 24 individuals per 50 square meters and 6 common chokecherry individuals per 50 square meters. The mean number of species encountered along the point cover transect was 9.8 and 12.3 respectively for study area and the Collom aspen reference area samples. Average herbaceous production in the aspen type was 1,152 lbs. / acre oven -dry forage. Converting oven to air dry forage by a factor of 1. 11, yields 1,278 lbs. / acre available herbaceous air-dry forage. Assuming a 50 per cent utilization factor and 900 lbs. / acre cattle animal unit, the cattle carrying capacity was 0.71 AUM's per acre. For sheep the carrying capacity was 4.26 AUM's per acre. Mountain Shrub - The mountain shrub vegetation type occurs on a moisture gradient lying between the aspen and the sagebrush -grassland vegetation types. On the mesic end of the type, Gambel oakbrush was dominant while common chokecherry was co -dominant with serviceberry. On the xeric end, serviceberry was dominant and western snowberry was co -dominant. The mountain shrub type occurred throughout the study area, but was most abundant and continuous south of West Fork. North of West Fork the type was less continuous and as elevations decrease to the north was found only in isolated areas on steep north facing slopes where moisture conditions were more favorable. The mountain shrub type was identified by the dominant presence of serviceberry or Gambel oakbrush (Figure 3.3 of Exhibit 10, Item 5). The reference area for the mountain shrub vegetation type was located in section 30 on a ridgetop with east and west facing slopes at an elevation of approximately 8,000 feet. The reference area was partially dominated by serviceberry and oakbrush (Figure 3.4 of Exhibit 10, Item 5). Total vegetation cover within the mountain shrub study area samples averaged 79.3 percent (Table 3.5 of Exhibit 10, Item 5). Bare ground averaged 5.6 percent and litter and rock was 15.0 percent combined. Mean shrub cover was 42.9 percent, more than half the total vegetation cover. Western snowberry was the dominant species with 24.9 percent cover. Serviceberry and Gambel oakbrush had 8.8 and 5.9 percent cover, respectively. Western snowberry had a significant presence in the samples because cover samples were taken from measurements made below a height of 4 feet. As such, samples were more a measurement of the understory of the type rather than the total canopy cover. Many of the serviceberry and oakbrush shrubs had heights exceeding 4 feet. Perennial grasses had a cover of 18.3 percent. Nodding brome, slender wheatgrass, and blue wildrye were the dominant grasses. Perennial forbs had a cover of 12.4 percent with silvery lupine the dominant forb. Other co -dominant forbs included western yarrow, nettleleaf horsemint, smooth fleabane and aspen peavine. Total vegetation cover within the mountain shrub reference area was higher than that of study area samples at 88.7 percent (Table 3.5 of Exhibit 10, Item 5). Bare ground was 2.9 percent and lower than study area samples. Litter and rock was also lower than study area samples at 8.9 percent. Shrub cover within the reference area was 36.8 percent. Western snowberry was the dominant shrub with 24.8 percent mean cover. Serviceberry and Gambel oakbrush had 5.9 and 3.9 percent mean cover respectively. Perennial forbs had the second highest cover as a group; 25.3 percent exceeding that of study area samples. Dominant forbs included silvery lupine, nettle -leaf horsemint, and American vetch. Perennial grasses had a mean cover of 20.9 percent. Dominant grasses included Kentucky bluegrass, nodding brome and blue wildrye. Mean annual herbaceous production from study area samples was 151.5 grams per square meter. Perennial grasses produced 80.1 grams per square meter with Kentucky bluegrass producing 46.3 grams and nodding brome producing 9.8 grams. Perennial forbs produced 61.9 grams with nettle -leaf horsemint, silvery lupine, one -flowered helianthella, leguminous forbs and other miscellaneous forbs comprising the majority of the forbs. Mean annual herbaceous production from reference area samples was 183.4 grams per square meter. Perennial grasses produced 81.6 grams per square meter of which Kentucky bluegrass produced 53.7 grams per square meter and nodding brome produced 17.5 grams per South Taylor/Lower Wilson - Rule 2, Page 44 Revision Date: 7/23/18 Revision No.: TR -123