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West E[k Mine <br />• dominated by Symphoricarpos rotundifolius (snowbeny) and occasional Rosa woodsii (Wood's <br />rose) individuals. Poa pratensis (Kentucky bluegrass) dominated the low herbaceous layer. <br />Many minor graminoid and forb species were also present in this layer. <br />Three life-forms were encountered during the sampling of the RPE azea. They included graminoids, <br />forbs, and woody shrubs. Seventeen individual plant species were identified during sampling. Five <br />species were graminoids, five were forbs, and seven were woody shrubs. Of the species <br />encountered, sixteen were perennial and one was annual. All graminoid species encountered were <br />identified as cool season. Four of the five forbs were cool season, with the Solidago (goldenrod) <br />species being warm season. Woody species were divided in morphologic type, with five being <br />deciduous and two being evergreen. Fifteen species were native in origin and two were introduced. <br />None of the species encountered were designated noxious weed species. <br />Total vegetation cover of the RPE area was 82.00 percent. Based on cover sampling, graminoids <br />represented 2.93 percent mean cover (4.17 percent relative cover), forbs accounted for 1.47 percent <br />mean cover (1.26 percent relative cover), and woody plants represented 77.60 percent mean cover <br />and 94.57 percent relative cover. A summary of the cover sampling data is presented in Table 2, <br />Appendix M in Exhibit 70. <br />The dominant plant species in the oakbrush community was Quercus gambelii at 64.40 percent <br />mean cover (77.91 percent relative cover). All other species provided an order of magnitude less <br />cover than Quercus gambelii. Significant additional contributors to cover are as follows. <br />Symphoricarpos rotundifolius provided 5.33 percent mean cover and 7.17 percent relative cover. <br />Amelanchier alnifolia accounted for 2.80 percent mean cover and 3.97 percent relative cover. <br />Juniperus osteosperma provided 3.33 percent mean cover and 3.78 percent relative cover. In all, <br />these four species of woody plants accounted for 75.86 percent of mean total vegetation cover, and <br />92.83 percent of all relative vegetation cover. Only one graminoid species contributed significantly <br />to vegetation cover, Poa pratensis contributed 2.00 percent mean cover and 3.10 percent relative <br />cover. <br />Vegetative litter (prior yeazs growth, dead wood, and other biologic organic material) comprised <br />17.33 percent ground cover within the RPE azea. Baze soil was not encountered in the cover <br />sampling. Rock accounted for 0.67 percent of cover encountered in the RPE area. <br />Results of herbaceous production sampling in the oakbrush vegetation community are presented in <br />Table 3 of Appendix M in Exhibit 70. Mean total herbaceous production of the sampled quadrates <br />on the RPE area was 17.4 g/mZ (155.1 lb/ac.). Herbaceous production quadrat weights were highly <br />variable, with the standard deviation being 65 percent of the value of the herbaceous production <br />mean. When plotted, the herbaceous production values illustrated anon-normal distribution that <br />was bi-modal in nature. It may be hypothesized that low and variable levels of herbaceous <br />production within the oakbrush community can be attributed to the density of the shrub and tree <br />canopy, which effectively limits sunlight to the low growing herbaceous species. Field observation <br />noted that azeas of greater herbaceous production were correlated with openings in the canopy. <br /> As with vegetation cover, Quercus gambelii accounted for the majority of woody plants <br /> encountered. Quercus gambelii provided 123.3 stems/100 squaze meters (4988.4 stems/acre). <br />1.04-153 Revised November 2004 PRIO <br />