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as food by sandhill cranes this fall. In fact hundreds of cranes could be seen at a time foraging in alkali bulrush marshes. This species (as its common name indicates) prefers the more alkaline waters of the West and is common only where high salts occur. 4. Alpine rush meadow. Rushes {Juncus arcto-alpinus) dominate seeps and the seasonally wet soils along wetland margins. It is an open community with some bare ground exposed and low standing crops (approximately 100-200 g m'Z. 5. Salt Cedar Thickets. Salt cedar (Tamarix ramosissimum) and tall whitetop (Lepidium latifolium) dominate the dry portions of the study area. This community complex covers approximately 1/2 of the study area with nearly impenetrable thickets. Both of the dominant taxa are Eurasian natives which are noxious weeds along the upper Colorado River system. They have spread in areas that have been extensively disturbed. Disturbance can be caused by flooding, livestock grazing, or salinization of the land. In the study area large areas with bare soils created by flooding and heavy grazing and mowing were salinized by the rising water table created by irrigation fed springs. These salty soils are not suitable for the native woody plant species which are relatively salt intolerant. 6. Fremont Cottonwood Forests. Some decadent, and a few young, Fremont cottonwood (Populus fremontii) forests occur on site. The older forests are comprised of trees remaining from the more extensive cottonwood forests that existed on site pre- 1950. The younger cottonwoods may have become established in 1984 following extensive flooding by the Colorado River into the Escalante wetlands. The cottonwoods are established only on the wetland margins as they are intolerant of anaerobic soils. In addition, one river backwater channel, and the main river channel are distinct .habitats, but support no rooted vascular plant species. Algae are common on rocks in the backwater and main channel area. 31