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Fa deposits at higher elevations. They are more common at higher elevations and may exhibit seasonal or perennial flows. Rechazge comes from direct precipitation or snowmelt infiltration. Seeps and springs on steeper slopes typically support vegetation communities dominated by willows along with a variety of grasses and fortis. Seeps and r! springs on neazly level to moderate terrain, particulazly at higher elevations, support herbaceous communities dominated by such species as California false-hellebore, streamside bluebells (Mertensia ciliata), and various sedge species. A wetland shrub G component may be conspicuously lacking at the higher elevations due in some cases to the dense, competitive herbaceous stratum. Aspen typically provides a tree component where one exists, though this species is not a consistent indicator of wetland seep or f ;~ spring conditions. ~J Stockponds are man-made features which are filled either by flow from springs or overland runoff. Wetlands occurring in association with developed stockponds are typically limited to a narrow bank fringe, though more extensive wetlands may develop in the drainages leading to stock pond depressions. 'The wetland fringe is dominated primarily by spikerush (Eleocharis) and rush (Juncos) species. Other species such as small-winged sedge (Cazex microptera), clustered field sedge (Carex praegracilis), northwest cinquefoil and a variety of butter-cups (Ranunculus sp.) may also be present. A wetland shrub or tree stratum is rare, presumably as a direct result of animal use and/or C soil compaction from earthwork by dozers or other equipment. IZiDarlaII 7.OIIe9 C! Riparian zones occur along project area drainages and are chazacterized by comparatively narrow vegetation communities requiring wetter soil hydrologic conditions than the surrounding uplands. The boundaries of riparian zones are limited in width by the steep topography associated with drainage systems. These zones may or may not include a recognized wetland component. A variety of tree species aze usually associated with the riparian zones of the project area and, where occurring, the shrub component is denser than in the surrounding uplands due to soil moisture conditions. Recent studies in the semiarid west comparing riparian areas with adjacent uplands showed that riparian zones support up to 400 percent more plant biomass, up to 200 percent more species richness, ' and contribute to lazge increases in density and species richness for birds when compazed with upland areas (Clary and Medin, 1998). Douglas-fir (Pseudotsuga menzesii) dominates the drier portions of the riparian zone at lower elevations. Utah juniper (Juniperus osteosperma) and Rocky Mountain juniper (Juniperus scopulorum) also occur on drier sideslopes along with shrubs such as Gambel oak (Quercus gambelii), snowberry (Symphoricarpos oreophilus), servicebeny (Amelanchier alnifolia), chokecherry (Psunus virginiana), and red-osier dogwood. In more moist situations, tree species such as boxelder and narrow-leaf cottonwood are present. Aspruce/fir community is common to riparian zones of higher elevations. This community is characterized by Englemann spruce (Picea englemannii) and Colorado blue spruce (Picea pungens). Understory shrub components are similaz to those of lower elevations, though species such as Woods rose (Rosa woodsii) and thinleaf alder (Alnus incana temaifolia) aze somewhat more prevalent. Aspen becomes a co-dominant tree species as elevation increases and is the dominant species in wetter zones of the higher elevations.