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C~ecember 1.2003 <br />3.5 Vegetation <br />.r'a CjB ~-~ <br />For vegetation, the project impact area is the West Flatiron LBA tract area. The cumulative impact area <br />includes the area encompassed by the W est Elk Mine. <br />3.5.1 Existing Conditions <br />Several vegetation types exist within the LBA tract. These communities include Gambel oak vegetation, <br />aspen, spruce fir, Douglas fir, and scatterings of grasses and fortis. There are also rockslides and steep- <br />walled cliffs in the lease area that support little or no vegetation due to the surface expression of geologic <br />material. <br />3.5.9. ~ Riparian Vegetation <br />Riparian ecosytems typically occur along drainages where additional moisture (surface or ground water) <br />is available. They are transitional areas between terrestrial upland habitat and aquatic habitat. Riparian <br />areas are not necessarily associated with wetlands, which generally have prolonged soil saturation. For <br />purposes of this EA, the term "riparian" will be used to include aquatic ecosystems (wetlands) as well as <br />riparian ecosystems. In the lease tract, riparian zones would be narrow in width due to steep topography <br />and narrow drainage bottoms. <br />There is no "typical" vegetation for a riparian area; vegetation varies with elevation and exposure. A <br />spruce-fir community is common to riparian areas at higher elevations, and aspen may be co-dominant. <br />Boxelder and narrow-leaf cottonwood may dominate riparian areas at lower elevations. <br />Wildlife rely on riparian and wetland areas for many aspects of daily and long-term survival. Riparian <br />areas are typically cooler than the surrounding hill slopes and are important as sources of food and <br />protection. Such areas can attract a diverse composition of species. <br />Riparian surveys conducted in drainages proximate to the lease tract area provide information on <br />representative riparian conditions for the area (Greystone, 2001a and 2001 b). Riparian areas were <br />identified by the presence of aspen, bracken ferns and other characteristic understory vegetation or <br />distinct vegetation changes. Based on the Greystone surveys, riparian areas typically extend along part of <br />the entire bottoms of perennial and intermittent drainages. Such riparian zones vary in width, from 25 to <br />100 feet, and, in some cases, they include small ponds and small isolated wetland areas. Many of the <br />smaller ephemeral drainages may have no flow for several consecutive years and contain limited or no <br />r <br />riparian areas. <br />The Forest Service Watershed Conservation Practices Handbook (FSH 2509.25) discusses water <br />influence zones (WIZ). WIZ areas include the geomorphic floodplain, riparian ecosystem, and inner <br />gorge. Its minimum horizontal width (from the top of each stream bank) is the greater of 100 feet or the <br />mean height of natural dominant late-sera) vegetation. W IZ areas are shown on Figure 3-1, Geologic <br />Hazards Map. <br />tnvironmertal As~essn.ent <br />V4'ast Flatiron !_Bt~ Trect <br />G<<ni~isan G'aarity, C;niosado <br />