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Appendix A - Vegetation Sampling for Phase III Bond Release • (2) % Relative Cover of Species X = %Cover of Species X a/o Total Vegetative Cover Production was determined in 2005 by hand clipping six separate 0.1-square-meter quadrats along each 25-meter cover transect at meter-marks 2, 5, 9, 12, 14, and 22. The first production quadrat on each transect was not clipped until after the cover sample-point along that portion of the transect was taken. Production data collected in 2006 involved hand clipping one 0.5-square-meter quadrat along each 25- meter transect utilizing the following methodology: quadrats clipped on the reclaimed areas were placed to the right side of meter-mark 4; quadrats clipped in each reference area were randomly located along each individual transect. The quadrat location along each transect conducted in the reference areas in 2006 is displayed in Table A-1. Each of these data collection locations for 2006 are displayed on Figure 3. Vegetation was clipped and separated by life-form and desirability (perennial grass, annual grass, perennial fort, less desirable perennial forb, annual forb, and biennial forb), with the species alfalfa (Medicago sativa) separated from other perennial forbs. Less desirable perennial forbs are defined as the two weeds listed on the Colorado state list of noxious species (Canada thistle and field bindweed on List B and C, respectively). However, these forbs were not considered noxious in the project area because they are not noxious weeds on the Las Animas County list. Clipped vegetation was initially separated and weighed to the nearest 0.1 gram with the corresponding "wet" weight recorded. In 2005, the six quadrats per transect were averaged, resulting in an individual production value per sample (transect). The "wet" weights for each sample were utilized in the field to determine that an adequate number of samples had been collected. The clipped vegetation was then oven- dried and re-weighed as a field "dry" weight. The dry weights were converted to pounds per acre for each sampled area. Fifteen transects per sampling unit were initially conducted prior to evaluation of sample adequacy. Sample adequacy for vegetative cover and herbaceous biomass production within each sampling unit was determined using the Snedecor-Cochran sample adequacy formula (Equation 3). (3) tz s2 N` in _ (d x )2 Where: Nmin = the minimum number of transects or quadrats needed, the a = .10 t-table value for a single-tailed t-test with n-1 degrees of freedom, s2 = the sample variance, d = .1 (level of precision for estimate of the mean to be within 10 percent of the actual mean), and, x = sample mean 2215_GoldenEagle_PH3BOND 2006 3-10-08.doc A-2