Laserfiche WebLink
2.4 Determination of Woody Plant Density <br />Belt transects were employed tiD obtain a reasonable estimate of the woody plant density of the <br />North Dedine Area and Greasewood Reference Area. At each of the 20 sample sites in these arms, a 2- <br />meter wide by 50 meter long belt transect was established in the direction of the next sampling point <br />(typically in a cardinal compass direction -see Fgure 1). Then within each belt, all woody plants <br />(shrubs, trees, subshrubs, and succa~lents) were enumerated by spedes and age loss. Determination of <br />whether or not a plant could be counted was dependent upon the location of its main stem or root collar <br />where it exited the ground surface with regard to belt limits. A Yotal of 20 belt transects were sampled <br />for each unit. Sample adequacy was determined for informational purposes only. <br />2.5 Sample Adequacy Determination <br />Sampling of the revegetated units and reference area was restricted to 20 samples for cover and <br />woody plant density and 15 samples for production due to the managerial nature of collected data. <br />However, for informational purposes, sampling adequacy (n,,,ia) has been calculated for each variable in <br />each sampling unit in accordance with the promulgated Colorado guideline (April 18, 1995) formula for <br />sample adequacy when statistical testing is not required, as follows: <br /> <br />Where: n =the number of actual samples collected with a minimum of 15 in each unit; <br />t =the value from the t distribution for 9l)% confidence with n-1 degrees of freedom; <br />s z =the variance of the estimate as calculated from the initial samples; <br />x =the mean of the estimate as plculated from the initial samples. <br />SNOWCAP COAL COMVANY Page 6 Revegetation Evaluation 20D4 <br />