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• 2.0 METHODS <br /> 2.1 Vegetation Mao o �1 ?... � `ff. <br /> The study area was surveyed during the 1979 field season in order to <br /> identify and delineate vegetation community types, based on species composi— <br /> tion and physiognomic structure. The community types were then depicted on <br /> a topographic base map at a scale of 1 in = 1,000 ft; aerial photographs were <br /> also used during the mapping process. Additional information presented in <br /> the vegetation map (Figure 2) includes cover transect and production plot <br /> locations, reference area locations, and permit and study area boundaries. <br /> The vegetation map is provided in a pocket at the back of the report. Figure 3 <br /> is an enlargement of the wash plant , shop, and office complex at a scale of <br /> 1 in. = 400 ft. <br /> 2.2 Sample Design <br /> 2.2.1 Location of Sample Sites <br /> Data for cover, production, shrub height and density, and tree <br /> height , diameter, and density were collected along randomly located transects <br /> within systematically selected sample areas. The systematic selection of <br /> sample areas was used because most anticipated disturbance has already occur— <br /> red. It therefore was desirable to obtain the bulk of quantitative data from <br /> stands adjacent to, and representative of , the existing affected areas Prior <br /> to disturbance. It should be noted, however , that stands more remote from <br /> affected areas were also visited in order to determine the variability of <br /> each community type within the study area and to ensure as complete a species <br /> list as possible. <br /> 2.2.2 Collection and Analysis of Cover Data <br /> Vegetation cover was estimated in 1980 using a point—intercept <br /> method (Mueller—Dombois and Ellenberg 1974) . Data were collected at twenty <br /> sample points located at 5 m intervals along the transect and 0.75 m on <br /> either side of the transect midline. Each point—intercept reading was obtained <br /> by viewing through a vertically oriented sighting device mounted on an <br /> adjustable tripod. Fine cross—hairs in the sighting device were used for <br /> optimum point definition,. <br /> At each sample point , the first upward (overstory) or downward <br /> (understory) hit along a vertical line—of—sight was recorded as vegetation (by <br /> species, rock , litter , or soil . Vegetation intercepted below the first hit <br /> was recorded seoarately. Since only first hits were used in calculating <br /> percent cover, the data should be interpreted as representing "canopy cover" <br /> or "crown cover" rather than composite total cover. <br /> • <br /> -J- <br />