2021-12-22_PERMIT FILE - C1981019A

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RULE 2 PERMITS gram. Wet weights determined in the field were used to facilitate the collection of an adequate sample where necessary. Determination of Woody Plant Density - Documentation of woody plant densities in the grassland type (and associated reference areas) involved a total count of the shrubs within the entire area subject to sampling, or within large macroplots that occupy a substantial portion of the area subject to sampling. Implementation of this enumeration technique involved circumscribing the boundaries of the target polygon with hip chain thread and a sub-meter GPS unit. Once a target polygon was circumscribed, a team of two or more biologists walking shoulder to shoulder traversed the area enumerating each plant by species. The person farthest inside the line of observers trails hip chain thread to mark their path to prevent missing or double counting specimens on subsequent passes. The distance between observers is usually 15 feet or less depending on the height of grasses and the presence of low growing taxa. Constant communication among crew members precludes double counting or missing of plants located along the margins of observed paths. Sample Adequacy Determination- Sampling within the grassland community type and reference areas for ground cover and production was conducted to a minimum of 20 samples. From these initial samples, a mean and standard deviation for each variable was calculated. Where statistical testing is required, collection of an adequate sample(nmin)is typically necessary to insure reliable estimates of the population (e.g., estimates to within 10% of the true mean (µ)with 90% confidence). Where statistical testing is not required (10 ground cover transects in each of the other dominant communities) sample adequacy was calculated for informational purposes only. The Cochran formula below was utilized in accordance with directives in Colorado's guidelines (1988). When the inequality (nmin < n) is true, sampling can be considered to be adequate,and nmin is determined as follows: nmin=(t2s2)/(0.1 X )2 Where: n = the number of actual samples collected with a minimum of 20 in each unit; t = the value from the t distribution for 90% confidence with n-1 degrees of freedom; s 2 = the variance of the estimate as calculated from the initial samples; = the mean of the estimate as calculated from the initial samples. If the initial minimum number of samples in each area did not provide a suitable estimate of the mean (i.e., the inequality was false), additional samples were collected until the inequality (nmin < n) became true. This latter circumstance was necessary for collection of an adequate sample for the variable of production within the grassland community area. Detailed Vegetation Information General - As indicated above six native floral assemblages (community types) and two land use types were delineated within the vegetation study area. Boundaries between plant communities and land use types were delineated from aerial imagery and were confirmed or adjusted through on the ground verification techniques. In certain instances the original delineations from the existing Colowyo permit were significantly modified and in other circumstances little modification resulted. Results of these delineations are presented on Map 4. Acreages and relative distribution for each community / land use type within the vegetation study area are presented in Table 2.04.10-8. Floristic surveys of the vegetation study area resulted in the identification of 31 species of grass or grasslike plants, 81 species of forbs, and 22 species of woody plants for a total of 134 taxa (Table 2.04.10-9). None of these were determined to be sensitive, rare, threatened, or endangered, however, 3 South Taylor/Lower Wilson—Rule 2,Page 51 Revision Date: 12/20/19 Revision No.: TR-135