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u <br />• <br />• <br />The second method, total enumeration, is employed when the size of a unit was less than <br />approximately one acre in size. None of the 18 units evaluated in 2004 was subject to this second <br />method. This method involved total counts of woody plant populations as opposed to estimates of mean <br />densities through statistical sampling. Implementation of the total count technique involved <br />circumscribing the boundaries of the target polygon with hip chain thread. Once a unit was <br />circumscribed in this manner, a team of two or more persons walking shoulder-to-shoulder traversed the <br />plot enumerating each plant by species and age doss. The person farthest inside the line of observers <br />trails hip chain thread to mark their path to prevent missing or double counting specimens on subsequent <br />passes. The distance between observers is usually 15 feet or less depending on the height of grasses <br />and the presence of low growing taxa such as rose or snowberry. Each internal observer also "zigzags" <br />as they progress, occasionally fuming to view the area just passed to ensure visual coverage of the entire <br />portion of the plot for which they are responsible. Constant communication among crew members <br />precludes double counting or missing of plants located along the margins of observed paths. Age classes <br />recorded for both this protocol as well as the belt transects include: 1) seedling (plant of the year), 2) <br />young (typically 2-3 years of age), 3) mature, 4) decadent (plants with less than 25% live crown), and 5) <br />dead. <br />5.0 Determination of Seedling Emergence <br />Emergent density was measured at each sample point in the 2003 reclamation areas (35 total <br />sample points or approximately one sample for every two acres of revegetation). At each sample point, <br />five one-square foot quadrats were blindly tossed to the ground and the number of emergentr rooted <br />within the perimeter of each were recorded accordingly into one of five classes: perennial grass, <br />perennial fort, shrub, annual grass, or annual fort. Where possible recognizable taxa were recorded by <br />species. With the five replicates at each sample point a total of 175 quadrats were recorded. <br />6.0 Same Adequacy Determination <br />Sampling within each managerial unit was conducted to a minimum of 5, 15 or 20 samples per unit. <br />From these preliminary efforts, sample means and standard deviations for total non-overlapping <br />vegetation ground cover and woody plant density were calculated. For non-monitoring applications, the <br />typical procedure is that sampling continues until an adequate sample, np,;n, has been collected in <br />aaordance with the Cochran formula (below) for determining sample adequacy, whereby the population <br />is estimated to within 30% of the true mean (p) with 90% confidence. <br />Kenne~on Energy/Colowyo coal company AA$ Revegetatbn MOnitorrng-zoos <br />