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1 <br />The Osgood Sand Reference Area was measured and mapped in the field in 1994, and a <br />scaled drawing of the reference area was drawn. On the scaled drawing, a Cartesian <br />coordinate grid (50x50 feet) was established. Computer generated random numbers <br />were used to establish a pool of x,y coordinates. Fifteen random sample locations were <br />established for the reference area. Sample sites were located in the field through <br />compass triangulation and pacing from known landmarks. Figure 2 illustrates sample <br />point locations at the Osgood Sand Reference Area. <br />FIELD SAMPLIIVG <br />,, Vegetation Cover <br />' Vegetation cover was estimated by the use of the point-intercept method. An oculaz <br />point frame (ESCO Associates) was used to minimize instrument error and maximize <br />precision and observer accuracy. Cover transects were ZS meters in length, with two <br />sample data points collected at 1,0 meter intervals along the transact on opposite sides <br />of the transact centerline, 1.Sm apart. Transact direction was established randomly <br />through the use of a spinner. In no event were transacts allowed to extend within ten <br />' feet of reference or revegetated area boundaries to minimize impacts from "edge <br />effect. " <br />' • For statistical purposes, each cover transact (comprising 50 data points) served as a <br />sample unit. Data points recorded the first vertical "hit" on vegetation (above or below <br />' the instrument), soil (bare ground), rock, or litter. Subsequent "hits" on vegetation <br />were also recorded. Cover data were recorded and reported by individual plant <br />species. The first interception was used to calculate total vegetation cover values. <br />' Additional interceptions were used to calculate relative cover of individual plant species <br />and lifeforms. The quantitative cover data also provided the basis for calculation of <br />species composition and relative importance. <br />Herbaceous Productiou <br />' Herbaceous production was estimated by the harvest method. One herbaceous <br />production plot was located and randomly oriented at the origin of each cover transact. <br />Additional production plots were randomly located. Herbaceous production plots were <br />' 0.25 square meters in area. All current year above ground live herbaceous plant <br />biomass was clipped within the 0.25 square meter quadrat. Perennial grasses, annual <br />' grasses, and annual, biennial, and perennial fortis were separated and reported by <br />lifeform. Succulents, suffrutescent, and woody plants were not sampled. Production <br />material was air dried until weights varied by no more than O.lg. <br />!~~ <br />' -3 <br />