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transect length). The SCC-assigned number of samples for a given parameter in a given area <br />reflected previously experienced sample variability or the level of precision required for that area. <br />• <br />In the extended reference areas, each reference unit was gridded and numbered. Grid cell size <br />was 200 feet X 200 feet. These grid cells were placed contiguously by hand on maps of 1:4,800 <br />scale. Sample locations were selected as the center points of grid cells selected using random <br />numbers generated by computer. <br />Sample points were located in the field using topographic maps. Cover and woody plant density <br />transects were located and oriented using a blind throw of a meter stick. The final location of <br />each herbaceous production plot was chosen with a blind throw of the sampling hoop made from <br />the origin of the associated cover/woody plant density transect. At each cover/woody plant <br />density sampling location, the slope (percent) and aspect of the site were determined and <br />recorded, as was the orientation of the transect (in degrees not corrected for magnetic <br />declination). <br />SAMPLE ADEQUACY CALCULATIONS <br />Sample adequacy calculations for parameter estimation without hypothesis testing were carried <br />out using the formula as prescribed by the Colorado Mined Land Reclamation Board for <br />parameter estimation without hypothesis testing (CDMG 1995): <br />L J <br />ta 2 s2 <br />Nmin= ------------ <br />(d x )2 <br />where: <br />to = one-tailed t-value with (n-1) degrees of freedom, a=0.10 <br />2 <br />s = sample variance <br />d = 0.1 (0.15 for woody plant) (level of precision or desired detectable reduction) <br />x = sample mean <br />• <br />4