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Additional vegetation communities include a sedge (Juncus sp.)/Olney's bulrush (Scirpus americanus) community and tamarisk (Tamarix sp.) community. For the purposes of this report, the term wetland is used to describe the open water- aquatic, hardstem bulrush, flooded willow, and sedge/Olney's bulrush communities. The open water-aquatic community occurs in the central and southern portions of the site. Few submerged aquatic vegetation species occur in this community. Cattail (Typhus sp.) stands were drowned in the 1993 flood (Figure 4, photo). Large stands of hardstem bulrush occur surrounding the open water-aquatic communities. These bulrush communities occur in water up to three feet deep in the central portion of the Preserve (Figure 5, photo). The flooded willow community is the most unique (Cooper 1994) because it is dominated by black willow (Sali.x nigra) which reaches its northern limit in the Rocky Mountain Region near Moab. Stands of large (60 feet tall) black willow occur in the eastern and southern portions of the Preserve in standing water up to two feet deep.The stands of black willow are visible in historic aerial photos from 1950. Young black willow also occur regularly in these areas indicating regeneration (Figure 6, photo). Backwater and river communities were unvegetated except for the occurrance of algae (Figure 7, photo). The sedge/Olney's bulrush community occurs in the east central area of the Preserve. Soils are saturated to the surface with little standing water. The tamarisk community covers the northwest portion of the Preserve. The vegetation in this area has become dense following flooding of the Preserve in 1983 and 1984. Stands of cottonwoods (Populus sp.) are interspersed within the tamarisk in the northeast portion of the Preserve. This area is topographically lower than the northwest side of the Preserve. The river bank, the vegetated river sand bars, and the banks of Mill Creek are all dominated by dense stands of tamarisk (Figure 8 and 9, photos). Conclusions: Aquatic vegetation communities on the Preserve provide potential invertebrate habitat and cover for young razorback sucker. 10 h 1 1