2010-12-17_REVISION - C1981019 (160)

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followed by mountain big sagebrush and mountain snowberry at 355 and 340 plants per acre, respectively. The Juniper Scrub community is visually dominated by Juniper trees with assorted shrubs, grasses, and forbs occupy the areas between the trees. Most of this community is located on steep, relatively barren and erodable soils along the drier, northern edge of the study area. A small portion of this community can be found on the flat tops on the slopes where it intergrades into the sagebrush- dominated uplands. The juniper trees appear healthy and expanding into both the mesic and xeric sagebrush areas that are adjacent to this community type. 3.4.2 Juniper Scrub Reference Area The Juniper Scrub reference area is located just north of the study area boundary on a low rolling mesa top and adjacent west-facing moderately steep slope. This area was selected as a reference area because of limited extent of the community in the vicinity of the study area, reasonable access, low probability of future disturbance, and it represents a combination of two aspects that is similar to a majority of the area delineated as Juniper Scrub with the baseline study area. Review of Table V6 and Chart V1 indicates that the average vegetation cover of the Juniper Scrub reference area was 31.4%. Litter and rock provided an average of 24% and 14.1% of the ground cover, respectively, while bare ground exposure averaged 30.6%. The dominant plant species were Griffith's wheatgrass, Wyoming big sagebrush, thrifty goldenweed (Stenotus armeriodes), and cheatgrass with 5.8%, 5.0%, 2.8%, and 2.4% of the ground cover, respectively. Perennial plants (excluding noxious weeds) contributed 85% of the total plant cover (26.65% average cover) while annual species and noxious weeds contributed 15.1% and 0.0% of the composition, respectively. Perusal of Table V10 indicates that a total of 7 perennial species contributed at least 3% relative cover or composition (3% is the typical lower limit for plant diversity bond release evaluations). Three of those species were grasses, one was a forb, and the remaining three were shrubs. Review of Tables V11 and Chart V3 indicates that the average herbaceous production of this area in 2005 was 182 pounds per acre, oven-dry weight. Eighty-nine percent (162 pounds per acre) of the total herbaceous production is attributable to perennials, with grasses contributing 117 lbs./acre, forbs providing 40 lbs./acre, and sub-shrubs adding 5 lbs./acre. Eleven percent (20 pounds per acre) of the total production is attributable to annuals, with grasses contributing 6 lbs./acre and (orbs providing 14 lbs./acre. Noxious weeds were not found in any of the sampling quadrats in this community. CIZDAR MMIEK AMOCTAT95, INC. Page 24 2005 Collom Vegetation Survey