2025-02-27_PERMIT FILE - C1981018 (4)

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3. METHODS • a. VEGETATION MAPPING The final vegetation map for the Deserado Mine Permit Area (Maps 9 and 10, Pocket) was drawn at a scale of 1"=500' (1:6,000). The map was produced from topographic mapping and aerial photography of the site. The map contains 13 mapping units including 7 vegetation types with 4 vegetation complexes. Affected and reference area sampling sites are located on the map, as are important political and topo- graphic features. Each reference area shown on Maps 9 and 10 are 200' x 200' and are fenced with metal posts and sheep fence (6"x6" mesh). The fence is approxi- mately five feet high with one or two strands barbed wire around the top. b. SAMPLING SITE SELECTION Affected and reference areas (Table 1) were chosen for sampling in the laboratory using a random selection procedure. This technique consists of overlaying a grid on a base map or aerial photograph containing information concerning the distri- bution of vegetation communities. The grid was subdivided into areas corresponding • to affected sites and potential reference sites. A series of random number pairs were generated for each subdivision of the grid. The random number pairs were then used to plot points on the map according to a vertical and horizontal number index. Sampling sites were then located in the field according to the plotted positions. C. PHYTOSOCIOLOGICAL STUDIES Structural and compositional features of the vegetation types occurring in each of the affected types and reference areas were sampled in permanently marked tran- sects. Detailed methods for sampling accomplished in each vegetation layer (herb, shrub and tree) and for primary productivity measurements are discussed below. Sampling was conducted during August and September of 1980 and June of 1981. General information recorded for each vegetation type includes aspect: slope; and notations on special terrain features, land use and total 0 (rev. 5/86) II.F-5