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River and no flooding would have occurred. The Green River dike is in-place and can be clearly seen. The "wetland area" contained no standing water at all and much bare soil is exposed. There is .little water seen on the escarpment slopes where today strong springs occur, thus the springs may have been intermittent or not as strong as today. Definite grazing and pasture utilization lines from fences can be seen on the bottoms indicating differential use. There are many more cottonwoods on the bottoms than exist today. There are also some shrubs, most likely sandbar willow (Salix exictua), on the bottoms. Clearly, the vegetation and hydrologic patterns observed in this photograph are very different than occur today. We feel that little open water wetland would have occurred at this time. 1952 (22 August). This was a high flow year for the Green River. On the date of this photograph,-water levels in the wetlands were very high, higher than we observed during 1993. By 1952 irrigated agriculture was well-developed on the terraces to the east. The practice was to flood irrigate pastures using water diverted from the Green River on the east side of the terrace. The escarpment springs are flowing quite well in the area south of the modern wetlands, which may be due to irrigated fields in that area. The vegetation patterns observed at this time indicate conditions similar to what occurs today. Thus, the hydrologic regime of the existing wetlands may have been established sometime between 1937 and 1952. 1961 (25 September). This was a low runoff year on the Green River yet the water levels in the wetlands were similar to what we observed on nearly this same date in 1993. Thus, flooding in the wetlands does not appear dependant upon the Green River, Irrigation practices appear to be flood irrigation and the acreage irrigated has increased somewhat. 1969 (12 September). Green River flows during 1969 were similar to those of 1961. The area of irrigated agriculture has increased dramatically. There has been a significant decrease in the number of cottonwood trees in the wetland area, most likely due to drowning from sustained soil saturation. 1980 (27 June). Center pivot sprinklers have been installed on the terrace, and we assume they were first used between 1976 and 1979. Springs in the southern area have dried up perhaps because of reduced application rates in small areas (sprinkler vs. flood irrigation). By this time the cottonwood trees are greatly reduced in the wetland area, and it attains the site vegetation is very similar to today. Other vegetation changes appear to be the spread of salt cedar in the area. In the Moab, 5