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RULE 2 PERMITS <br />diversity estimates. Second hits on litter, rock, or bare soil were ignored. Only first -hits were used for the <br />determination of ground cover. <br />Plant identification and nomenclature follows Weber and Wittman 1996, Winward 2004, and USDA <br />Forest Service 1977. <br />Current Annual Herbaceous Production - At each production sample site, current annual herbaceous <br />production was collected from either 1 meter squared (m2) (Juniper Scrub type) or 1/2 m2 (all other types) <br />quadrat frames placed one meter and 90 degrees (0) to the right (clockwise) of the ground cover transect. <br />All above ground herbaceous vegetation of the current year growing within the vertical boundaries of the <br />frame was clipped and bagged separately by the following life form categories: Perennial Grass, Perennial <br />Forb, Noxious Weed, Annual Grass, Annual / Biennial Forb, and Sub - shrub. <br />All production samples were returned to the lab for drying and weighing. Drying occurred at 1050 <br />Celsius (C) until a stable weight was achieved (24 hours). Samples were weighed to the nearest 0.1 gram. <br />Woody Plant Density - At each sample site in the baseline inventory area and at 30 of the 40 production <br />sample points in the reference areas, a 2 -meter wide by 50 -meter long belt transect was established to <br />determine woody plant density. All shrubs, sub -trees (e.g., Gambel's oak) and trees were enumerated by <br />species. Determination of whether or not a plant could be counted was dependent upon the location of its <br />main stem or root collar where it exited the ground surface with regard to belt limits. Sample adequacy <br />was determined for informational purposes only. <br />Aspen Density & Canopy Cover - At each ground cover sample site in the aspen reference and baseline <br />areas, the point- center - quarter (PCQ) method was used to determine aspen density. At each sample point, <br />the surrounding area was horizontally divided into four quarters (quadrants) using the cardinal compass <br />directions (northeast, northwest, southeast, and southwest quadrants). Within each quadrant, the distance <br />to the nearest aspen (at least 5 feet in height) from the sample point was measured to the nearest foot (Y,). <br />Using the following equation, an aspen density was determined from these four measurements: <br />Aspen Density ( /ft2) = 3 /[7c(Y12+ Y22+ Y32+ Y42) /4] <br />At each sample point, canopy cover was visually estimated. Aspen canopy at over half the sample points <br />was substantially reduced due to the recent die -off of mature trees (most likely due to the recent drought). <br />Sample Adequacy Determination — A minimum of 20 samples were placed within each community type <br />of both the baseline and the reference areas. Ground cover and production information was collected at <br />each location. From these initial samples, a mean and standard deviation for each variable was calculated. <br />Where statistical testing is required (for the establishment of qualified reference areas), collection of an <br />adequate sample (nmin) is typically necessary to insure reliable estimates of the population (e.g., <br />estimates to within 10 percent of the true mean (g) with 90 percent confidence). The Cochran formula <br />below was utilized in accordance with directives in Colorado's guidelines (1988). When the inequality <br />(nmin < n) is true, sampling can be considered to be adequate, and nmin is determined as follows: <br />nmin = (t2S2) / (0.1.x )2 <br />Where: n = the number of actual samples collected with a minimum of 20 in each unit; <br />t = the value from the t distribution for 90 percent confidence with n -1 degrees of freedom; <br />s 2 = the variance of the estimate as calculated from the initial samples; <br />z = the mean of the estimate as calculated from the initial samples. <br />Cullom — Rule 2, Page 59 Revision Date: 9/28/11 <br />Revision No.: PR -03 <br />