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11.0 Exhibit J — Vegetation Information <br /> Figure 5, Exhibit C3 depicts the location and types of vegetation at the mining site. Figure <br /> 6 through Figure 8 show photos from the property. <br /> 11.1 Existing Vegetation Communities <br /> The existing vegetation found on the Rifle Gravel Pit Permitted Area consists primarily of <br /> upland pastures, with a small component of riparian wood land/shrubland dominated by <br /> Russian olive (Elaeagnus angustifolia). The property also includes wet meadows and <br /> wetlands/marshes that are outside of the Permitted Area. Dominant species that typify each <br /> community are listed in Section 4.4 for additional information. The entire property supports <br /> generally continuous ground coverage of>80% throughout, and standing biomass and <br /> productivity are relatively high for the surrounding region. <br /> Noxious weeds observed at the property include cheatgrass (Bromus tectorum), Russian <br /> olive, chicory (Cichorium intybus), halogeton (Halogeton glomeratus), Russian knapweed <br /> (Acroptilon repens), and bulbous bluegrass (Poa bulboua). The weed species constitute a <br /> significant portion of the vegetation in upland pasture areas within the property, but <br /> generally were not observed to form monotypic stands or to present an unusual risk of <br /> infestation. The weed component and prevalence on the property is typical of grazed <br /> pasturelands in the surrounding area. <br /> A comprehensive noxious weed survey has been completed for the property, and it is likely <br /> that other common weeds in the surrounding area would be found in a dedicated search, <br /> including hoary cress (Cardaria drabs), field bindweed (Convolvulus arvensis), common <br /> mullein (Verbascum thapsus) and several thistle species. A copy of the Noxious Weed <br /> Report is included in Attachment C. <br /> Vegetation types, quantitative cover estimates, and relationship to soil types were based on <br /> a comprehensive wetland delineation that was performed for the property at the request of <br /> the USACE. This comprehensive delineation effort was based on the direct measurement of <br /> vegetation, soil, and hydrology conditions along regularly-spaced transects, resulting in a <br /> sample grid of 183 points spaced at 100-foot intervals, covering the entire Affected Lands <br /> and the majority of the parcel as well. <br /> • Tree Stratum: consists exclusively of Russian olive, comprising approximately 5% <br /> cover of the Affected Lands. Minimal evidence of reproduction; individuals are <br /> generally mature specimens 20-30 feet tall <br /> • Sapling/Shrub Stratum: includes primarily greasewood (Sarcobatus vermiculatus) <br /> and rubber rabbitbrush (Ericameria nauseosa), with small areas of big sagebrush <br /> (Artemisia tridentata) in more xeric micro-sites. Total coverage is approximately 25% <br /> of the Affected Lands, with average height being approximately 3 feet tall. <br /> • Herb Stratum: dominant species include alkali sacaton (Sporobolus airoides), inland <br /> saltgrass (Distichlis spicata), and intermediate wheatgrass (Thinopyrum <br /> intermedium). Other representative species as described in Section 4.4. Total <br /> coverage is generally 80-90%, approaching 100% coverage in some areas. Total <br /> herbaceous vegetation heigh and abundance has increased notably in the last two <br /> growing seasons since cattle grazing has been curtailed on the property, with <br /> average heights of approximately 2 feet currently. <br /> 62 <br />