2010-12-17_REVISION - C1981019 (160)

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• • transect, the transect orientation was turned 90° in the appropriate direction so the transect could be completed within the target unit. In this manner, edge transects were retained entirely within the target unit by "bouncing" off the boundaries. Production quadrats were always oriented 90° to the right (clockwise) of the ground cover transect and placed one meter from the starting point so as to avoid any trampled vegetation. Woody plant density belts were extended parallel to the ground cover transects for a distance of 50 meters. 2.3 Determination of Ground Cover Ground cover at each sample point was determined utilizing the point-intercept methodology as illustrated on Figure V-1. As indicated in this figure, Cedar Creek utilizes state-of-the-art instrumentation it has pioneered to facilitate much more rapid and accurate collection of data. A transect of 10 meters length was extended in the direction of the next sampling location from the flagged center of each systematically located sample point. At each one-meter interval along the transect, a "laser point bar" was situated parallel to, and approximately 1.5 meter vertically above the ground surface. A set of 10 readings was recorded as to hits on vegetation (by species), litter, rock (>2mm), or bare soil. Hits were determined at each meter interval by activating a battery of 10 low-energy specialized lasers situated along the bar at 10 centimeter intervals and recording the variable intercepted by each of the vertically- projected, narrow (0.02") focused beams (see Figure V-1). In this manner, a total of 100 intercepts per transect were recorded resulting in 1 percent cover per intercept. To facilitate diversity calculations, "second-hit" data on plants were recorded where an overstory (shrub stratum) was intercepted first. In these circumstances (after being recorded), the overstory hit was moved aside to facilitate a determination of the "second-hit" in the herbaceous stratum, and in the case of a plant intercept, it would be recorded by species. However, second hits on litter, rock, or bare soil were ignored. Only first- hits were used for the determination of ground cover. This methodology and instrumentation facilitates the collection of the most unbiased, repeatable, and precise ground cover data possible. Plant identification and nomenclature follows Weber and Wittman 1996, Winward 2004, and USDA Forest Service 1977. 2.4 Determination of Current Annual Herbaceous Production At each production sample site, current annual herbaceous production was collected from either 1 m2 (Juniper Scrub type) or 1/2 m2 (all other types) quadrat frames placed one meter and 900 to the right (clockwise) of the ground cover transect to facilitate avoidance of vegetation trampled by investigators CEDAIRCREIEKAMICMT7ES, INC. Page 8 2005 Collom Vegetation Survey