2001-12-11_PERMIT FILE - C1980005 (5)

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PIxJDUCPION FSTINTFITES Field Techniques. Circular wire exclosures, approximately 1.5 m in diameter and 1.5 m high were situated at each randomly located sample '-- point during early May, 1979. Domestic livestock were kept off the area until exclosures were established. All exclosures were constructed of 2"x4" mesh wire to prevent grazing by all medium-sized (i.e., rabbits) and large mammals. fScclosures were supported by '~" steel reinforcing rods and labeled as described previously for cover quadrats. Initially, the number of production exclosures established in each vegetation type and control area was the same as the number of cover quadrats (Table 1); however, te,io production exclosures in the mixed brush type/ aspen subtype affected area were disturbed during the gracing season and not sampled. The nwnber of production exclosures placed in each vegetation type was determined by r~thods described under "Data Collection" above. Exclosures Caere left in place throughout the 1979 gracing season. All exclosures were sampled on both affected and control areas during the period August 9 through September 6, 1979. All production samples were wllected late enough in the day to ensure that the vegetation surface was dry. This procedure ensured the accuracy of wet weight determinations. Production plots were sampled using a 1 m2 welded aluminum frame quadrat centered within each exclosure. All present-year vegetation growth falling within the 1 m2 quadrat was clipped using priming shears (shrubs) and grass scissors (fortis and grasses). All shrubs were clipped near ground level to ensure accurate separation of the present year's gra~ath in the laboratory prior to drying and weighing. F~cperience has derronstrated that new graath can be separated accurately and efficiently only in the laboratory where enviroiurental influences such as wind can be controlled. The current year's gro•.ath clipped from each protected quadrat was bagged according to major species or life form and properly labeled. Wet weights were recorded by vegetative species and by Life form for all species except shrubs using spring scales at the ~• time of clipping. -11-