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<br /> <br /> <br />1 <br /> <br />1 <br /> <br /> <br /> <br /> <br />1 <br /> <br />1 <br /> <br />1 <br />1 <br /> <br /> <br />3.0 RESULTS AND DISCUSSION <br />3.1 REVEGETATED AREAS DESCRIPTION <br />The revegetated area all occur on moderately steep, east-facing slopes <br />in an area that was once vegetated by pinyon-juniper woodland. Today the <br />area is characterized by cool season bunchgrasses and annual and perennial <br />forbs. <br />Total absolute vegetation cover ranged from 44 to 70 percent and <br />averaged 56.1 percent (Table 1). Perennial grasses accounted for 35.7 <br />percent absolute cover, perennial forbs accounted for 12.4 percent, annual <br />forbs provided 7.7 percent, and annual grasses provided only 0.3 percent. <br />Bare soil averaged 22.0 percent, while rock and litter averaged 12.5 and <br />9.3 percent cover, respectively. <br />Perennial grasses comprised 64 percent of the relative vegetation <br />cover. The dominant species were western wheatgrass (Agropyron smithii), <br />a native, with 11.6 percent absolute cover and slender wheatgrass <br />(A ropyron trachycaulum) with 9.7 percent cover. Other major grasses <br />were creste we atgrass (Agropyron desertorum) with 6.1 percent cover and <br />sideoats grams (Bouteloua curtipendula) with 3.9 percent cover. Other <br />common species were Indian ricegrass (Oryzopsis hymenoides), tall <br />wheatgrass (Agropyron elongatum), and smoo rome romopsis inermis). <br />Less common species inc~u ed pubescent wheatgrass (A~~ropyr~~on <br />trichophorum), red threeawn (Aristida longiseta), an~uirreltail <br />i anion ongifolium). <br />Perennial forbs accounted for about 22 percent of the relative plant <br />cover. Alfalfa (Medica4o sativa), a species of the revegetation seed <br />mix, was predominant, with~~percent absolute cover. Other common <br />species contributing to cover were two-groove milk vetch (Astragalus <br />bisulcatus) and gumweed (Grindelia sp.), both native colonizers. <br />Annual forb cover was surprisingly low (7.7 percent absolute cover). <br />The major species present were yellow sweetclover (Melilotus <br />officinalis), another legume of the seed mix but now found throughout the <br />permit area, with 2.9 percent cover; prickly lettuce (Lactuca serriola) <br />with 2.1 percent cover; and Russian thistle (Salsola i erica) with 2.0 <br />percent cover. Other species present included common sunflower <br />(Helianthus annuus) and skyrocket gilia (Ipomopsis aggregata). <br />Annual graminoid cover was very low (0.3 percent) and comprised of <br />Japanese brome (Bromus japonicus) and cheatgrass (Bromus tectorum). <br />Numerous shrub species are colonizing <br />in low densities. These included fourwing <br />mountain mahogany (Cercocarpus montanus), <br />(Chrysothamnus nauseosus), broom snakeweed <br />Gambel oak (Quercus gambelii). <br />the area, but are present only <br />saltbush (Atriplex canescens), <br />rubber rabbitbrush <br />(Gutierrezia sarothrae). and <br />-4- <br />