2006-12-18_REVISION - M1978314 (3)

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King Mountain Sand and Gravel Mine Ecological Resources Assessment Page 11 Table 2. Noxious Weeds Common Name Scienti is Name Habitat Abundance Canada thistle Cirsium arvense Riparian shrubland, Common Graminoid Wetland, Disturbed Sites, Aspen Forest scentless Matricaria perforata Disturbed Sites Uncommon chamomile cheatgrass (downy Bromus tectorum Disturbed Sites Uncommon brome) 4.5 Colorado Natural Heritage Program A records search for the vicinity of the Property was conducted of the online Colorado Natural Heritage Program (CNHP) data base for imperiled ecological communities and for threatened, endangered and sensitive plan[ species (Colorado Natural Heritage Program 2006a and 2006b). There are three Potential Conservations Areas (PCAs) within a few miles of the Property: Cabin Creek PCA and Sunnyside Creek PCA, which are approximately 6 miles southwest of the Property, and Stifel Creek PCA, which is approximately 9 miles southeast of the Property. The Cabin Creek and Stifel Creek PCAs have occurrences of the rare plant Harrington beardtongue (Penstemon harringtonii), ranked as vulnerable in the state of Colorado by CNHP (G3/S3); it is also on the sensitive plant lists of the US Forest Service and the Bureau of Land Management (CNHP 2006b). The habitat of this plant is open sagebrush or, less commonly, pinyon- juniper habitats. Soils aze typically rocky loams and rocky clay loams derived from coarse calcareous parent materials, and elevation ranges from 6800-9200 ft. (Spackman et al. 1997). As the soils on the Property are derived from Quaternary gravels and not the calcareous substrates found in the PCAs, the probability of occurrence of Harrington beardtongue on the Property is very low. Several riparian shrubland communities dominated by Booth's willow are tracked by CNHP, ranked as vulnerable in Colorado, and known to occur in Routt County (Cazsey et al. 2003}. These include a Booth willow/mesic graminoid shrubland documented in the Sunnyside Creek PCA mentioned above, a Booth willow/mesic forb shrubland, and a Booth willow/beaked sedge shrubland. One or more of these communities, or other similaz willow communities, aze likely present on the Property. More detailed vegetation sampling would be required to identify the specific community on this fine a scale. Additional information about the Sunnyside Creek PCA is included in Appendix 2B. Definitions of the CNHP status codes aze also found in Appendix 2B. 4.6 Range Condition According to Mike ]ones the property was part of the larger Hewes Ranch, and the property was subject to grazing by 300 horses. After acquisition by King Mountain Gravel, LLC, the property was rested in 2005. The property was grazed this summer under lease to the Hogan family from Boulder. According to the Mountain Loam range site description reviewed above in Section 4.3, under pre-settlement conditions grass, in association with minor amounts of woody plants such as sagebrush and snowberry and several fortis, should account for most of the vegetative cover. Dominant grasses are Idaho and/or Arizona fescue, slender wheatgrass,