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Twenty Mile Mine Amendment - Baseline Vegetation Study Plan <br />2.4 Vegetation Cover <br />Line-transect point-intercept methods will be used to collect vegetation cover data as a percent <br />cover measurement. A transect ten meters in length will be established. Each ten meter transect <br />will represent a single sampling unit. <br />A total of 50 point-intercepts will be observed and recorded at two-meter intervals along the <br />sample transect. At each two-meter interval, cover measurements will be taken from ten point- <br />intercepts oriented perpendicular to the transect direction and centered over it. A point-intercept <br />frame with points set ten centimeters apart will be used to take cover readings, with the point <br />intercepts being projected vertically to the ground surface. Each point-intercept will be assigned <br />an absolute cover value of 2%. <br />Cover measurements will record "first-hit" point-intercepts by live foliar vegetation species, <br />litter, rock, or bare ground. Litter will include all organic material that is dead. Rock fragments <br />will be recorded when particle size is equal to or greater than a non-erodible particle size (about <br />'/4 inch in diameter). Point-intercept data will also be used for the plant species inventory. <br />Total vegetation cover data will be recorded by plant species. Total vegetation cover will be <br />reported in absolute percentages from the point-intercept data using the total ground cover <br />observations for each sample point. Relative vegetation cover percentages will be calculated <br />using the total vegetation cover data for each sample point. <br />2.5 Annual Herbaceous Production <br />Annual herbaceous production will be measured using standard clipping methods. Production <br />samples will be centered over the randomly established sample points. Samples will be taken <br />during the expected peak of the standing crop. This typically occurs during July through early <br />August. <br />Total annual herbaceous production will be measured by harvesting the annual herbaceous <br />biomass produced within a 0.5 square meter circular quadrat. Prior to clipping all species present <br />within the sample area will be identified. Next, herbaceous growth will be clipped as close to <br />ground level as practical, separated by life form, and placed in bags. <br />Production samples will not include full shrubs, subshrubs, succulents, Yucca spp., cactus, <br />designated or prohibited noxious weeds, cushion plants, trees, or species listed under the <br />Endangered Species Act. <br />Livestock grazing impacts on productivity samples will be controlled through the use of sample <br />enclosures centered over the sample points. Production sample enclosures will be placed prior to <br />the introduction of livestock or before the growing season in which baseline vegetation sampling <br />is to be conducted begins. <br />2.6 Shrub Density <br />Shrub composition and density will be measured using belt transects that are 10 square meters in <br />size (1 meter x 10 meters). Samples will be taken along the same transect used to collect cover <br />7