2016-08-08_PERMIT FILE - C1981019A (19)

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INTRODUCTION testing for woody plant density is not necessary (because performance standards have been set), this variable compared favorably as well. The grassland community exhibited a value of 509 plants per acre whereas the pooled data from the two reference sites averaged 451 plants per acre or about 90% of the study area grassland value. Mountain Shrub - As indicated on Map 413, the mountain shrub community within the Study Area occupies 378.11 acres (63%) and occurs throughout the area. The community is comprised of two primary subtypes: 1) xeric (dry) and 2) mesic (moist). The xeric subtype is typically found on the south, east, and southeast exposures and exhibits more dominance in the overstory by serviceberry. The mesic subtype is typically found on the north, west, and northwest exposures and exhibits more dominance in the overstory by Gambel's oak (Quercus gambellii) and choke cherry (Prunus virginiana). A total of 64 species were observed within the mountain shrub community with a distribution of 16 grasses, 37 forbs, and 11 shrubs. Average ground cover of vegetation (2005) within the study area was 64.1% with 1.2% rock, 28.6% litter, and 6.1% bare ground exposure. Dominant species included: Mountain snowberry (Symphoricarpos oreophilus), bluegrass, thickspike wheatgrass, goosegrass (Galium aparine), Nelson needlegrass (Stipa nelsonii), and mountain big sagebrush. The number of perennial herbaceous species exhibiting between 3% and 50% relative cover (composition) was determined to be 3 grasses and 0 fortis. The 2005 evaluation of the existing mountain shrub reference area showed that total plant cover was 51.3%. Production within this reference area in 2005 was found to be 801 pounds/ acre. As indicated on Table 2.04.10-10, in 1980 the herbaceous plant cover of the mountain shrub community was documented to be 41.9%, in 1988 was 56.67%, and in 1985 total plant cover was 79.3%. (Herbaceous plant cover for 1985 data cannot be segregated from total plant cover as the raw data are not presented in a manner that allows separation of 1s' hit vs. 2°d hit data.) Production in 1980 was 570 pounds per acre. In 1988 and 1985, production was 933 and 1,352 pounds per acre, respectively. Woody plant density for mountain shrub in 1980 and 1985 was determined to be 5,790 and 4,363 plants per acre, respectively. Based on the supplemental ground cover values above, it would appear that the mountain shrub community from the Lower Wilson Study Area (64.1% total plant cover) is comparable to the sampling of this community from 1980 and 1988 and the survey of the South Taylor area in 1985. Sagebrush - As indicated on Map 413, the sagebrush community within the Study Area occupies 116.56 acres (19.4%) and occurs throughout the area as "pockets" or "islands" within the mountain shrub type. Proposed activities will disturb an estimated 7.87 acres of this community that comprises 6.56% of the total disturbance. The community is comprised of two primary subtypes: 1) xeric (dry) and 2) mesic (moist). The xeric subtype is typically found on the more skeletal soils of south, east, and southeast exposures and along the perimeters of wind-swept ridgelines. The mesic subtype is typically found on the deeper soils of north, west, and northwest exposures and on more level areas. A total of 61 species were observed within the sagebrush community with a distribution of 16 grasses, 35 forbs, and 10 shrubs. Average ground cover of vegetation (2005) within the study area was 63.1% with 3.5% rock, 17.8% litter, and 15.6% bare ground exposure. Dominant species included: Mountain big sagebrush, Basin big sagebrush, bluegrass, Mountain snowberry, tailcup lupine, western wheatgrass, and thickspike wheatgrass. The number of perennial herbaceous species exhibiting between 3% and 50% relative cover (composition) was determined to be 3 grasses and 1 forb. The 2005 evaluation of the existing sagebrush reference area showed that total plant cover was 51.8%. Production within this reference area in 2005 was found to be 620 pounds per acre. South Taylor/Lower Wilson — Rule 2, Page 54 Revision Date: 11/19/15 Revision No.: PR -04