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RULE 2 PERMITS <br /> 40,4,rw..v"k'".. A' 67.' e' <br /> threatened or endangered. Detailed descriptions of the six identified major vegetation community types <br /> and their sub-types, and qualitative descriptions of the minor communities/land use types are presented in <br /> Table 2.04.10-33. <br /> Major Vegetation Community Types <br /> Values for species diversity, production, and woody plant density are summarized by community type. <br /> Table 2.04.10-35 lists those species by community type found to represent from 3 percent to 50 percent <br /> relative cover (including second hits below the shrub layer). Table 2.04.10-36 displays vegetation <br /> production by community type, and Table 2.04.10-37 compares woody plant density of baseline and <br /> reference areas by community type. Table 2.04.10-38 shows the statistical comparison between baseline <br /> and reference areas by community type. <br /> Aspen - The aspen community within the Vegetation Study Area occupies 770 acres. It is found at higher <br /> elevations on steep slopes and throughout drainage bottoms that generally exhibit northeast to northwest <br /> aspects. Soils are typically well-developed. The aspen reference site is located adjacent to the <br /> southwestern corner of the Vegetation Study Area boundary and occupies 68.7 acres (Map 4). This <br /> reference area represents the variety of site characteristics seen throughout the aspen community type in <br /> the Vegetation Study Area. It was also selected as a reference area because of its accessibility and the low <br /> probability of future disturbances. <br /> A total of 63 plant species were observed within the aspen community baseline study area while the <br /> reference area exhibited 41 taxa. No sensitive species were observed within this area. The noxious <br /> weeds Canada thistle(Cirsium arvense)and houndstongue (Cynoglossum officinale)were observed in the <br /> study area(Table 2.04.10-39). <br /> The average vegetation ground cover within the aspen community baseline study area was 75.45 percent <br /> with 0.0 percent rock, 19.97 percent litter, and 4.59 percent bare ground exposure. Dominant plant <br /> species and percent cover included: mountain brome (Bromus marginatus) with 13.86 percent, blue <br /> wildrye (Elymus glaucus) with 11.59 percent, bluegrass (Poa agassizensis) with 7.1 percent, mountain <br /> snowberry (Symphiocarpos oreophilus) with 6.72 percent, and nettleleaf giant hyssop (Agastache <br /> urticifolia) with 4.93 percent. Of the total plant cover, 96 percent (72.52 percent average cover) were <br /> perennial plants (excluding noxious weeds). Annual species contributed 4.0 percent and noxious weeds <br /> contributed 0.6 percent of the composition. Seven perennial species contributed at least 3 percent relative <br /> cover or composition (3 percent is the typical lower limit for plant diversity bond release evaluations), <br /> with three of those species being grasses,two forbs, and two shrubs(Table 2.04.10-39). <br /> The average herbaceous production within the aspen community baseline study area was determined to be <br /> 1,249 pounds per acre, oven-dry weight, with 98 percent (1,226 pounds per acre) as perennials (grasses <br /> contributing 771 pounds per acre and forbs providing 455 pounds per acre), and 1 percent(12 pounds per <br /> acre) as annuals (all forbs). The remaining 1 percent (11 pounds per acre) was comprised of noxious <br /> weeds(Table 2.04.10-40). <br /> Woody plant density in the aspen community baseline study area was 4,685 woody plants per acre with <br /> dominance by mountain snowberry (2,858 plants per acre) and chokecherry (Prunus virginiana) (1,111 <br /> plants per acre). The shrub lifeform accounts for 93 percent(4,346 plants per acre), sub-trees account for <br /> 2 percent (96 plants per acre) and trees account for 5 percent (243 per acre) of the total (Table 2.04.10- <br /> 41). <br /> The density of larger aspen averaged 139 trees per acre using the point-center-quarter(PCQ) method(the <br /> diffaranra batux,een the turn lin))ws was 1" t bran.rir rp — Ppt-tkp wei;e_7Pt <br /> recorded in the PCQ measurements). The canopy cover in the aspen community baseline study area was <br /> Collom—Rule 2,Page 48 Revision Date: 12/20/19 <br /> Revision No.: TR-135 <br />