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1 • Field descriptions from each of the 3 soil pits were used to determine soil <br />taxonomy to the soil series level. Preliminary NRCS map unit descriptions of <br />the Slocum loam and the Binco silty clay loam and their known inclusions <br />were used to determine the soil series (Appendix 2). As with all flood plains <br />in this area, flooding and the deposition and erosion of material maybe a <br />frequent occurrence (100-yeaz precipitation event). Frequent flooding, <br />channel movement, erosion and deposition have resulted in highly variable <br />soil profiles. <br />• <br />RESULTS <br />The soil descriptions and photographs for each soil pit are contained <br />Appendix 1. The primary soil parameters including bottom depth of rooting, <br />depth to the top of mottling and depth to surface of the groundwater table are <br />summarized in Table 1. <br />Table 1. Selected Soil Pit Parameters <br />Soil Pit # Depth of Rooting <br />(inches) Depth to Mottles <br />(inches) Depth to Water <br />(inches) <br />1 96 19 96 <br />2 67 34 67 <br />3 60 na na <br />Maximum root depth at soil pits #1 and #2 was observed into the seasonal <br />high water table. Mottling in the soil profile is a good indication of the depth <br />of the seasonal high water table. This high water table fluctuates with the <br />season and by year. Unconsolidated stream-laid sediments were observed at <br />96 inches in soil pit #1 and at 67 inches in soil pit #2. Both of these soil pits <br />exhibited water flow from these unconsolidated gravels and coarse sands. <br />Soil profiles from soil pits #1 and #2 also have an overthickened (cumulic) <br />mollic epipedon as a result of slow accumulation of material deposited from <br />occasional flooding. These soils have formed in positions where they receive <br />fresh sediments at a rate slow enough for the material to become incorporated <br />in the mollic epipedon. Enhanced vegetation growth and plant species <br />adapted to mesic sites was also evident adjacent to soil pits #1 and #2. <br />The maximum rooting depth at soil pit #3 was observed at a depth of 60 <br />inches, with a significant decline in roots noted at shallower depths due to <br />calcazeous horizons that restrict root development. No indicators of AVF soil <br />characteristics were evident in this soil pit. Reduced vegetation growth and <br />• production were evident from the plant species better adapted to arid sites. <br />2 <br />