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contributed relatively little to woody plant density; Symphoricarpos montanus (48/acre), <br />Pinus edulis (6/acre), and Juniperus osteosperma (3/acre). <br />• 3.2 QUALITATIVE EVALUATION <br />3.2.1 Pinyon Juniper Woodland <br />This vegetation community predominates from the edge of the flat colluvial bottom up the <br />side slopes of the dissected drainage basins. It is visually dominated by the tree species Pinus <br />edulis, and Juniperus osteosperma. This vegetation community is common throughout <br />southwest Colorado on xeric sites with shallow and/or rocky soils. Understory species are <br />less common as the tree and shrub canopy increase (CNAP, et al, 1998). There is often a <br />shrub layer present, comprised of a mix of species locally adapted and including, Quercus <br />gambelii (Gamble's oak), Amelanchier alnifolia (serviceberry), Cercocarpus montanus <br />(mountain mahogany), Purshia tridentata (antelope bitterbrush), and Ribes cereum (currant). <br />The herbaceous layer is scant and presence and production directly related to yearly and <br />seasonal precipitation. The most common graminoid herbaceous species include; Oryzopsis <br />hymenoides (Indian ricegrass), Bouteloua gracilis (blue grama), Sitanion hystriz (bottlebrush <br />squirreltail), and Poa secunda (Sandberg bluegrass). Forb presence is more ephemeral than <br />graminoid occurrence. Common species include Leucelene ericoides (sand aster), and <br />several Penstemon species (penstemon). <br />~ Vegetation cover of this community within the project area was estimated at between 60 and <br />70 percent with the majority of the total and relative cover originating from the tree and shrub <br />• layers. Herbaceous cover was estimated at ten percent, Underneath and adjacent to the tree <br />and shrub species, litter cover is common, however bare ground and rock predominate in the <br />inter-tree spaces. <br />The majority of biomass production occurs within the tree and shrub layers and is variable on <br />a yearly basis depending upon precipitation levels. In a brief review of annual production in <br />several studies, Clary (1986) found that total annual production ranged from 53-600 <br />pounds/acre, while graminoid production (in the same studies) ranged from 18-427 <br />pounds/acre. The wide variance in herbaceous production was linked to the variability in tree <br />density, with the greatest herbaceous production in the most open canopies. Herbaceous <br />production within the project area in this community was estimated at 50-100 pounds/acre <br />given the relatively dense tree and shrub canopy, and proliferation of rocky substrate. <br />Species composition of the pinyon juniper woodland was estimated to be equivalent in <br />numbers to the rabbitbrush/big sage mixed shrubland. From our observations, graminoid <br />numbers were neazly equal, though there was significantly less cover of Bromus tectorum and <br />the species mix was different (see above dominant species). There were a greater variety of <br />shrubs (identified above) and succulents (Yucca species and several cactus genera) than in the <br />rabbitbrush/big sage mixed shrubland. The few forbs noted were native to the pinyon juniper <br />woodland community, and not indicative of revegetation efforts or grazing impacts. <br />National King Loal LLG Page 6 <br />King II Mine 2005 Baseline Vegetation Report <br />