Laserfiche WebLink
"Guidelines for Compliance with Land Use and Vegetation Requirements for Coal Mining". A <br />species was counted for density if it was rooted within the belt. For all species except willow <br />stems were traced back to their origin and counted as one plant. For example, a sagebrush <br />plant that had 4 stems emanating from a central point was counted as one planUstem. A 3 ft. x <br />100 ft. belt, originating at the randomly-located sample point and extending in a random <br />direction, was used in the sagebrush type and dry land reference area. Arandomly-located 1 <br />square meter sampling frame was used for stem counts in the willow component of the <br />swale/drainage. All willow stems emanating from the ground were counted as it was <br />impossible to determine if any one stem belonged to any one plant. Fifteen samples were <br />collected in this manner. <br />Samale Adequacy 1987 and 1999. The following formula was used to determine the <br />adequacy of the quantitative cover, production, and woody density samples in the New Horizon <br />2 studies: <br />Nmin = (st)y/(dx)2 <br />where, <br />Nmin =minimum sample size <br />. s =sample standard deviation <br />= two-tailed t-value at the 90 percent confidence interval <br />(alpha = 0.10) with infinite degrees of freedom (t = 1.645) <br />d =desired level of reduction about the sample mean (0.10) <br />x =sample mean <br />In all cases, sampling was continued until the minimum sample adequacy requirements were <br />exceeded, or the prescribed maximum number of observations were collected. Maximum <br />sample sizes were developed during the consultation process with OMLR staff and CDMG staff <br />prior to and during the field studies (letter correspondence from Mr. Peter O'Connor to J. Lunan <br />of Peabody dated August 7 and September 3, 1987), (1999 site visits with Dan Matthews and <br />Harry Rainey, and phone conversations with Janet Binns all of the CDMG). <br />Livestock Carrving Caaacity. Stocking rates were calculated for the irrigated pasture <br />vegetation type only using the results of production samples collected in the type. The rates <br />. (REVISED 9/99) 2.04.10 - 24 <br />