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• higher number will be taken. When morz than thirty (30) cover sampler arz necxrsary, additional sets of five (5) points will be randomly distributed by mndamfy selecting five (5) of the thirty (30) BRB sxbdivisionr, and mndomly locating an additional point within each. Sampling was conducted between July 15 and August 31, 2005 and will occur during the same period in 2006. Cattle grazing on BRB and reference area sites will be deferred untl afrer the covet sampling is complete. Percent cover will be assessed at sample locations using apoint-intercept method. Points will be projected using a Cover-point Optical Point Projecror, Model 3. This optical device vertically projects a very fine point (approx. 0.07 mm); the projected point is intercepted either by plants, bare soil, rock (mineral matter > 1 cxn diameter), standing dead (plant material produced during a previous growing season and still standings or litter (fallen organic debris). These interceptions aze tallied at fifty (50) systematically distributed locations along a 50 m transect and 50 ctrl to each side of the sample transect. Hence a total of 100 points aze collected along each sample transect The Covet- Point Optical Point Projector is mounted on a tripod and configured so that the axis of point projection is 50 ctn from the center point of the tripod. Thus, if rotated 180°, two points exactly one meter apart can be projected from a single tripod placement Percent cover values that will be assessed include; % cover by plant species, % total vegetation cover, litter, % standing dead, % rock, % baze ground, and % total cover (vegetation plus litter plus standing dead, plus rock). At each sample location, a random orientation will be detemvned using the blind spin of a meter • stick or an azimuth derived from a glance at the second hand of a watch (and the value multiplied by six). A 50-m tape will be extended from the sample point in the random dtrection. The tripod on which the optical point projector is mounted will be placed over the tape at 1-m intervals. The arm of the projector will be oriented at 90° to the transect and adjusted to level using a bubble level so that the line of projection is vertical. After observing the polar and tallying the interception, the mounting bar will be rotated 180° for observation of a second point. Then the tripod will be moved to the next 1-m interval mazk along the tape until a total of 100 points aze tallied. At each sample point, after a "First Hit" interception by a plant species, the optical focus will be extended downward to determine whether these aze any further interceptions on other plant spedes. If so, these will be tallied by spedes as "Other Hits". Along each sample transect, the presence of less common spedes not hit during the point-intercept sampling will be documented by recording the presence of all plant spedes occurring within one meter on either side of the sample transect Thus, from each 50 m cover sample transect comes a measure of spedes "density" that can be expressed as a number of spedes per 100 squaze meters. "First Hit" percent cover at every sample location will be calculated for each plant spedes as well as rock, baze soil, and litter by dividing the total number of intercepts Eor each by the total number of points (100). Relative plant cover will be calculated by dividing the First Hit cover of each plant spedes by the total First Hit vegetation ewer. "All Hit" percent cover will be calculated for each plant spedes by dividing the total number of hits on a spedes (First Hits plus Other Hits) by the total number of points projected. Relative All Hit Covet will be calculated by dividing the All Hit cover for each species by the total All Hit vegetation cover. Cover data reporting will be organized by the following lifeform categories: • -Native Annual /Biennial Forbs -Introduced Annual /Biennial Forbs - Native Annual Grasses -Introduced Annual Grasses ESCO Associates 13-13-4 TA110 * 03/06