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Baseline Technical Report <br />ARCADIS Report for Soils and Biological <br />Resources, MLE2 Project Area <br />3.4 Natural Grassland <br />Natural grasslands account for approximately 164 acres (39 percent of the entire <br />survey area) and occur in Sections 2, 3, 4, and 6. This vegetation community is the <br />most frequent of communities in the survey area. Natural grasslands in the survey <br />area have a species composition and density that has not been substantially <br />changed as a result of disturbance. Cover is relatively high and ranges from 60 to 90 <br />percent. Natural grasslands occur on gentle slopes with a southern exposure. <br />Dominant species include Parry's oatgrass (Danthonia parryi), junegrass (Koelaria <br />macrantha), Kentucky bluegrass (Poa pratensis), mountain muhly (Muhlenbergia <br />Montana), squirreltail (Elymus elymoides), western wheatgrass (Pascopyron smithii), <br />bearded wheatgrass, and Arizona fescue. Grassy slope sedge (Carex oreocharis) <br />(once considered a rare species by the Colorado Natural Heritage Program, but not <br />currently) occurs relatively frequently in this vegetation community type on granitic <br />soils. Noxious weeds are generally not present or are sporadic in nature within <br />natural grasslands. <br />3.5 Disturbed Grassland <br />Disturbed grasslands account for approximately 10 acres (two percent of the entire <br />survey area), occurring primarily in Section 6, adjacent to an active mine site. These <br />grasslands have been disturbed in historical times (primarily as a result of older <br />mining activities) and continue to be disturbed by ranching practices (cattle grazing) <br />and road construction /adjacent mining operations. Disturbed grasslands occur on <br />gentle slopes with a southern exposure in the survey area. The composition, density, <br />and cover of vegetation (30 -60 percent) have been substantially altered. Dominant <br />species include Kentucky bluegrass, western wheatgrass, squirreltail, redtop <br />(Agrostis sto/onifera), junegrass, green needlegrass, Arizona fescue, and smooth <br />brome (Bromopsis inermis). Several noxious weed species are present, including but <br />not limited to Canadian thistle (Cirsium arvense), bull thistle (Cirsium vulgare), and <br />dalmatian toadflax (Linaria da/matica). <br />3.6 Riparian Woodland <br />Riparian woodlands (as mapped) account for only 5 acres (one percent of the entire <br />survey area); however, this community was not observed during the survey. <br />Saturated drainages /wetlands were also not observed due to the late- summer <br />(typically dry) timing of the survey. As such, riparian vegetation that may normally be <br />present during the spring was not observed during this late- summer survey. If <br />missed, but potentially present within the survey area, dominant tree may species <br />CCV Baseline Soils Biology Resource Report (11- 17- 11).doc 13 <br />