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• samples for a given parameter in a given area reflected previously experienced sample variability <br />or the level of precision required in a given area. Random numbers generated by computer were <br />used to select grid cells, in the middle of which a sample point was placed, and recorded on the <br />field maps. These sample points were located as accurately as possible in the field using aerial <br />and topographic maps and pacing from known locations. Cover and woody density transects <br />were located and oriented using a blind throw of a meter stick. Final location of each herbaceous <br />production quadrat was accomplished with a blind throw of the sampling hoop made from the <br />origin of the associated cover/woody plant density transect. At each cover/woody density <br />sampling location, the slope (percent) and aspect of the site (in degrees not corrected for <br />magnetic declination) were determined and recorded, as was the orientation of the transect (in <br />degrees not corrected for magnetic declination). <br />TWO-STAGE SAMPLING: <br />The Wadge Pasture was sampled for woody plant density using atwo-stage statistical design as <br />set fourth in Chapter 10 of Cochran (1977). Two-stage sampling is undertaken by dividing the <br />entire area to be sampled into smaller units of equal area that are known as "primary units". A <br />subset of primary units is randomly selected, and each selected primary unit is then divided into <br />"subunits". Randomly selected subunits are sampled and represent the second-stage of <br />• sampling. Wadge Pasture was divided into 20 equal-sized primary sample units and 15 of these <br />were randomly selected to be sampled (see Map 2). Each primary sample unit was <br />approximately 15 acres in size. Within each selected primary sample unit, three of the 607 <br />potential secondary units were randomly chosen in the same fashion that was used for single <br />stage random sampling. These points were then placed on the field maps and located as <br />accurately as possible in the field. Three woody plant density samples were placed in each of the <br />fifteen primary units for a total 45 woody plant density quadrats. For statistical purposes, sample <br />size (n) is fifteen. <br />Sample Adequacy Calculations <br />Sample adequacy calculations parameter estimation without hypothesis testing were carried out <br />using the formula as prescribed by the Colorado Mined Land Reclamation Board (CMLRB 1995): <br />iz sZ <br />Nmin= -'--___' <br />(d x )2 <br />