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IV. MINOR PLANT COMMUNITIES • Wetland (Relict Ozbow) Within the RPE area there is one wetland vegetation community located south of the State Ntghway 133 right-of--way and generally in the center of the RPE area (Figure 4). This wetland area is located at the lowest elevation within the RPE azea (approximately 6080' above MSL). Areal extent of this area is approximately 0.7 acres. This wetland area and associated vegetation community appears to have originated as an oxbow of the North Fork of the Gunnison River. Since this area is currently ten to twenty feet above the current level of the North Fork of the Gunnison, it would be a relict oxbow structure. The wetland has been isolated from the North Fork of the Gunnison River by the construction of the earthen embankment supporting State Highway 133. The source of water which supports a wetland vegetation community in this area is postulated to be surface water runoff from the RPE area slope and toeslope, as well as surface runoff from the adjacent roadway. Given the presence of outcropping bedrock springs above the North Fork of the Gunnison River at approximately this elevation, the wetland community may be additionally supplied with subsurface water through interconnection with fractures or springs. The only drainage exit from the wetland area is a road culvert which has been blocked by animal activity, therefore the only avenues of exit are evapotranspiration and seepage. • Vegetation of the wetland community is characteristic of swamps or marshes with relatively stagnant hydrologic conditions, and is dominated by old and senescent Populus angustifoGa (narrowleaf cottonwood) individuals along the edges of the wetland, numerous Salix sp. (willow) clumps along the edges extending to the center, and a dense mixture of Typha latifolia (cattail), Carex sp. (sedges), and Agros[is alba (redtop). Approximately the west third of the wetland had standing water present in September, while the remainder of the area was subirrigated (no standing water on the surface, but saturated conditions below the ground surface). • Total vegetation cover of this community was estimated between 50 and 65 percent. Herbaceous production was approximated to be between 200 and 300 g/m2 (1780-2675 Ib/acre). Woody plant density was estimated at 1000 stems/acre, dominated by the willow thickets. The small size and relative inaccessibility of this area and vegetation community significantly limit its potential uses. Size of this community, as well as unpredictable subirrigation and/or surface flow effectively limits its usefulness as pasture or hayfield. While the community serves as wildlife habitat for residents of the RPE azea, the adjacent North Fork of the Gunnison provides a more diverse and high quality wildlife habitat. -10-