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A single developed field of Improved Pasture (23.5 acres) that has not yet reverted back to a natural <br />community is located in the southeastern portion of the study area where a relatively flat bench of <br />shrubland / forest has been cleared and planted primarily to smooth brome (Bromus inermis) and <br />thickspike wheatgrass (Agropyron dasystachyum). Based on preliminary planning, it does not appear <br />that this area would be disturbed by potential mine operations. Based on a total of 3 sample points, <br />vegetation cover within this area was 81.3% with smooth brome, thickspike wheatgrass, and tailcup <br />lupine representing 58.6%, 19.3%, and 10.3% of the composition, respectively (data not presented in <br />this document). Sampling for current annual production documented a considerable 3,082 pounds per <br />acre for this area, and the woody plant density totaled only 40 shrubs per acre. <br />The Improved Pasture reference area comprises 11.1 acres and is located along lower Morgan Creek <br />northwest and external to the vegetation study area boundary (see Map V1). This area was selected as <br />a reference area because of its elevation, ease of access, low probability for future disturbance, and the <br />fact that it represents a species "composition" similar to that which was planted in early mine reclamation <br />(1970's, 80's, and early 90's) at the existing Colowyo operation. Mine revegetation from this period <br />typically included "improved" varieties or genotypes of both introduced and native species that exhibit <br />better germination, larger growth form, and/or have more efficient nutrient uptake. A primary purpose in <br />the establishment of such a reference area is to provide additional options for bond release evaluations <br />by providing an area comparable in "improved" species and shrub density to post-mine grazing land uses <br />with regard to early revegetation at Colowyo. Such a post-mine land use is also possible at the Collom <br />project, though unlikely at this stage of planning. <br />As indicated on Table V1, a total of 12 plant species were documented from this reference area with <br />no sensitive species being observed. The noxious weeds Canada thistle and whitetop were observed in <br />this reference area. Plates V23 and V24 provide photographic documentation of this reference area at <br />the time of sampling. <br />Review of Table V9 and Chart V1 indicates that the average vegetation cover of the Improved <br />Pasture reference area was 74.0%. Litter and rock provided an average of 19.6% and 0% of the ground <br />cover, respectively, while bare ground exposure averaged 6.5%. The dominant plant species were <br />smooth brome, crested wheatgrass (Agropyron cristatum), and povertyweed with 57.1%, 8.4%, and <br />3.2% of the ground cover, respectively. Perennial plants (excluding noxious weeds) contributed 99% of <br />the total plant cover (73.5% average cover) while annual species and noxious weeds contributed 0.6% <br />and 0.1% of the composition, respectively. Perusal of Table V10 indicates that a total of 4 perennial <br />• <br />CEDAR MMI&F.A&&SOCM7 S, INC. Page 32 2005 Collom Vegetation Survey