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1 <br /> <br /> <br /> <br />Vegetation Sampling For 1993 <br />Two eference~plots were established by WFU during the summer of 1990. One plot has <br />a northern exposure and one has a southern exposure. Within each exposure, four 100 by <br />100 foot plots were constructed and seeded as described in the Study Plan Design section <br />above. Vegetative sampling was conducted on 19 and 20 July 1993. <br />Methods <br />1 <br /> <br /> <br /> <br /> <br /> <br />1 <br />1 <br />t <br /> <br /> <br />1 <br /> <br />Vegetative sampling was conducted using 100 ft. long point-intercept transects. The actual <br />number of transects conducted in each of the areas was determined by a systematic design <br />which was agreed upon by DMG prior to going to the field. Five transects were randomly <br />located on a line extending along the uphill axis of each reference plot. Transects were laid <br />across the plots perpendicular to the base axis. Sample adequary was calculated using the <br />Snedecor-Cochran sample adequacy formula (Equation 1). <br />t= s~ <br />Nm, _ - <br />(dx): <br />(1) <br />Where: <br />N = required number of transects or quadrats, <br />r = the t„~ value for adouble-tailed t-test with n-1 degrees of freedom at the 90% <br />confidence level, <br />s2 = sample variance, <br />d = 0.1 (the level of precision for estimate of the mean to be within 10% of the <br />actual mean), and <br />x = sample mean. <br />Sample adequary was reached on each plot in five transects except on plot Nl where ten <br />transects were required to reach sample adequary. <br />Ground cover was evaluated along each transect by sampling two points, one meter apart, <br />at 4 foot intervals along each transect. This method was used instead of the 10 point frame <br />due to the close proximity of transects, variability of cover in some plots, and the utilization <br />of these same transects for the woody plant density analysis. Cover was classified as <br />vegetation, litter, or rock. Lack of cover was classified as bare soil. Vegetation was further <br />classified by species. Each transect consisted of 50 sample points. Each point was <br />determined by projecting acover-point optical point projection device (model 2) vertically <br />downward to the sample location on the transect and recording all "hits" on vegetation. The <br />10 <br /> <br />