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Herbaceous Cover <br />The herbaceous layer cover was visually estimated from <br />randomly located 1.Omz quadrats. Total plant cover (including lichens and <br />.sses), cover by litter and rock, and cover by bare soil were estimated. <br />These three components sum~ed to 100 percent for each of the quadrats. Cover <br />was also evaluated on a different basis in which the total cover for each quadrat <br />was greater than 100 percent. This second approach takes into account the <br />overlap that occurs among the different vegetation components. for example, <br />litter occurs underneath growing plants and may form a nearly continuous layer <br />in the ground layer. Using the first method (~~ihere all components add to <br />100 percent), only that portion of litter not covered by a vegetation canopy <br />would be estimated. With the second approach the actual amount of litter <br />present in the quadrat would be estimated. The only requirement using the <br />second method is that the cover by all components must equal at least 100 <br />percent. .With the second approach, cover by vegetation, lichens, mosses, <br />fitter, <br />~ bare soil, rock, and cover by each species were estimated. By obtaining <br />ata for each species it is possible to obtain a measure of species diversity <br />based on the number of species per square meter. <br />Preliminary statistical tests were made in the field to insure requirements <br />for sample adequacy were met. Final statistical analyses for sample adequacy <br />were completed in the laboratory. In order to locate sampling points in the <br />affected area, a grid was superimposed on the vegetation map. Pairs of random <br />numbers obtained from a random numbers table (Steel and Torrie 1960) were used <br />to locate quadrat coordinates. In the control areas a steel tape was laid along <br />one axis. Pairs of random numbers from a random numbers table were used to locate <br />sampling points. The first number located a point along the tape and the second <br />number was a paced distance perpendicular to the tape. <br />~~rub Cover and Density. Shrub cover, frequency and density were obtained using <br />2 <br />