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community types such as sagebrush utilized a larger grid with dimensions of 2,000 X 2,000 feet. <br />Intermediate sized communities utilized grid dimensions of 1,000 X 1,000 feet. Smaller communities <br />utilized a 500 X 500 foot grid dimension. Statistical adequacy calculations as detailed in Colorado's <br />guidelines will be utilized to insure that an adequate sample for ground cover and production is obtained <br />from samples collected in this manner. If insufficient samples are provided for any given type and/or <br />variable by the first systematic effort, an "inter-grid" will be established to facilitate collection of additional <br />samples for that type/variable in an equally unbiased manner. <br />Once a selected grid point is located in the field, ground cover sampling transects are always <br />oriented in the direction of the next site to be physically sampled to further limit any potential bias while <br />facilitating sampling efficiency. This orientation protocol follows that which is indicated on Figure V-1. If <br />the boundary of an area is encountered before reaching the full length of a transed, the transact <br />orientation will be turned 90° in the appropriate direction so the transact can be completed. In this <br />manner, boundary transacts are retained entirely within the target unit by "bouncing" off the boundaries. <br />Production quadrats are always oriented 90° to the right (clockwise) of the ground cover transact and <br />placed one meter from the starting point so as to avoid any trampled vegetation. Woody plant density <br />belts extend parallel to the ground cover transact for a total length of 50 meters. All three sampling <br />protocols will be utilized during the first round of systematic sampling efforts. Thereafter, any additional <br />sampling for statistical adequacy using an "inter-grid" will only involve the "inadequate" variable(s). <br />2.3 Determination of Ground Cover <br />Ground cover at each sample point is determined utilizing the point-intercept methodology as <br />illustrated on Figure V-1. As indicated in this figure, Cedar Creek utilizes state-of-the-art instrumentation <br />it has pioneered to facilitate much more rapid and accurate collection of data. A transact of 10 meters <br />length is extended in the direction of the next sampling location from the center of each systematically <br />located sample point. At each one-meter interval along the transact, a "laser point bar" is situated <br />parallel to, and approximately 1.5 meters vertically above the ground surface. A set of 10 readings is <br />recorded as to hits on vegetation (by species), litter, rock (>2mm), or bare soil. Hits are determined at <br />each meter interval by activating a battery of 10 low-energy specialized lasers situated along the bar at <br />10 centimeter intervals and recording the variable intercepted by each of the vertically-projected, narrow <br />(0.02' focused beams (see Figure V-1). In this manner, a total of 100 intercepts per transact are <br />recorded resulting in 1 percent cover per intercept. Second hits on herbaceous material below any shrub <br />stratum are used only to provide improved precision regarding diversity. This methodology and <br />instrumentation facilitate the collection of the most unbiased, repeatable, and precise ground cover data <br />possible. Plant ID and nomenclature follows Weber and Wittman 1996, and USDA Forest Service 1977. <br />CEDAR CREEK ASSOCIATES, Inc. Page 3 Cullom Vegetation Methodology <br />