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Figure 2. Diagram of Stanton, ND Soil Wedge (Doll et al., 1984). The basic design <br />presented in the diagram is replicated 3 times. Step 1 is the layout of the subsoil <br />material and Step 2 is the layout of the topsoil material. Length of wedge is <br />approximately 243 m. Each subplot is approximately 4 m wide. <br />Methods and Materials <br />1236 <br />Siep 1 <br />Step 2 <br />Preparation for vegetation and soil sampling in June and July of 2003 involved the removal <br />of cattle from the study areas by the middle of May, 2003. North and south baselines on the <br />ZSW were established at 0.5 meters from the north boundary and 8.1 meters from the south <br />boundary because of deterioration of edges of the wedge. Boundaries of the toe -, mid- and <br />shoulder -slope positions were determined based on geomorphology of the slope and documented <br />as distances from north and south baselines. A stratified random sampling design with a baseline <br />was used to determine plot locations (Chambers and Brown, 1983; Vogel, 1987). Two random <br />production plots were chosen in the toe of the wedge, four plots in the mid - section of the wedge <br />and two in the shoulder- position. Number of plots in each slope position was chosen based on <br />the size of the area being sampled to achieve adequate representation of vegetation production <br />for each position. Five basal cover readings, used to determine diversity values, were taken with <br />a 10 -pin point frame in toe -, mid- and shoulder slope positions to give a total of 15 frames per <br />subplot. A total of 384 production plots and 720 10 -pin point frame readings were taken at the <br />ZSW site. <br />A baseline for the SSW was established 0.5 meters from the base of the wedge. Boundaries <br />of toe -, mid- and shoulder -slope positions were determined based on geomorphology of the slope <br />and documented as distances from the baseline. The same sampling strategy used at the ZSW <br />was used at the SSW to give a total of 96 production plots and 180 10 -pin point frame readings. <br />Diversity was determined for both sites from cover data with Shannon's Diversity Index <br />(Magurran, 1988) <br />