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0%WWW <br /> "01— ingsnouncxnioa�, <br /> Soil Depth. Over fifty holes were dug in the 1977 and 1978 terraces to determine <br /> soil depth classes. From observations on these holes, two depth classes, shallow <br /> and deep, were apparent. The shallow class is defined as having up to an 18 cm (7 <br /> inches) soil cover. The deep class is greater than 18 cm (7 inches) soil cover. <br /> More than 200 holes were ultimately dug in conducting this study. In spite of the <br /> large number of observations, neither the delineation of more than two soil depth <br /> classes nor the mapping of distinctly separate shallow and deep areas was possible <br /> due to the heterogeneity of soil cover on the terraces. <br /> In order to provide accurate correlation of vegetation sampling with soil depth, at <br /> least four observation holes were dug at each randomly located vegetation <br /> sampling site. Vegetation sampling sites were individually classified as shallow or <br /> deep based on the average of the observed soil cover. Slope and aspect at each <br /> vegetation sampling site were also recorded. Soils information is presented in <br /> Table 2. <br /> Vegetation Sampling. Vegetation was sampled for production by clipping current <br /> year's growth from randomly located square meter quadrats. Forbs and grasses <br /> were harvested separately. Each sampling site was classified according to soil <br /> depth, and sampling continued until five deep and five shallow sites were sampled <br /> in each year. Clipped samples were weighed in the field. At least two grass and <br /> forb samples per day were returned to the lab to determine oven-dry basis moisture <br /> percentages. Production figures given in this report are based on oven-dry weights. <br /> Cover and production measurements are shown in Table 3. <br /> Cover was measured using fifty-point transects. Point hits were recorded as <br /> individual plant species, rock, litter, or bare ground. Transects were located <br /> adjacent to production quadrats. A complete sample consisted of five transects. <br /> In general, transects ran along the contour. Relative cover by species for each <br /> year is given in Table 4. <br /> 4 <br />