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Sampling was conducted from July 25 - August 27, 2005 by and/or under the direct supervision of <br />Cedar Creek's Senior Range Ecologist Steven R. Viert and Plant Ecologist, Mr. Erik M. Mohr. Depending <br />on area and variability the vegetation variables of ground cover, production and woody plant density <br />were determined with between 20 and 76 samples for each community type. In addition to these <br />quantitative efforts, current conditions at the time of sampling were documented by several photos (see <br />Plates V1- V34) to provide a visual demonstration of site-conditions at the time of sampling. <br />1.2 Background <br />The Collom Vegetation Study Area (13,605 acres and about 20 miles southwest of Craig, Colorado) <br />occupies the south-central headwaters of the synclinal Axial basin (along the Danforth Hills) and <br />generally drains to the northeast, eventually into the Yampa River which is tributary to the Green then <br />Colorado Rivers. Elevations in the study area range from just below 6,400 feet +/- above mean sea level <br />where Jubb Creek exits the study area to 8,567 feet at a high point along the ridge to the south. Based <br />on precipitation records from the nearby Colowyo mine, precipitation ranges from an estimated 12 inches <br />per year in the northern lower elevation areas to over 25 inches along the higher elevation ridgelines <br />along the southern portion of the study area. Typical stream gradients in the headwaters range from 3 <br />to 5 percent but occasionally exhibit steeper reaches, and 1 to 3 percent along the alluvial / colluvial <br />floodplains lower in the watershed. Adjacent upland drainage side slopes range from moderately steep <br />to steep (>35 % slope) whereas the "benches"' between drainages generally exhibit flatter slopes with a <br />northeasterly aspect between 1 and 5%. Land uses noted in the area include: wildlife habitat, <br />agriculture (grazing by cattle and sheep), coal exploration, and recreation. Most of the recreational land <br />use is related to big game hunting that draws participants from across Colorado and the United States. <br />A majority of this study area is comprised of two dominant and reasonably distinct community <br />types, Sagebrush and Mountain Shrub (See Map V1), which are segregated primarily due to the influence <br />of elevation and related factors. The sagebrush community is principally found at lower elevation <br />occupying the relatively flat uplands (mesic sub-type) and steeper southeast-facing slopes (xeric sub- <br />type) on deeper more fine-textured soils. The mountain shrub community is primarily found at higher <br />elevations occupying the relatively flat uplands (xeric sub-type), steep south-facing slopes (xeric sub- <br />type), and steep northern-facing slopes (mesic sub-type) on shallower, but more developed soils. Four <br />other major vegetation communities occupy various niches within these two dominant community types. <br />The Juniper Scrub community is located on the steep slopes in the drier and rockier, northern portions of <br />the study area. Soils in this area are very thin and skeletal and have been subjected to elevated erosion <br />over the past several decades. The Bottomland community is an aggregate of vegetation sub-types <br />(wetland, riparian bottom, sagebrush, mountain shrub, and grassland) that are found in the relatively flat <br />CIEllDARCREEKAMOCIIATES, INC. Page 2 2005 Collom Vegetation Survey