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1 <br /> <br /> <br /> <br /> <br /> <br /> <br />1 <br /> <br />1 <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />1 <br />INTRODUCTION <br />This report presents the results of the 5rst year of final bond release sampling for cover, <br />production, shrub density and species diversity data for reclaimed and reference areas at the <br />Walden Coal Company Mine site located northeast of Walden, Colorado. The reclaimed areas at <br />the site consist of two parcels: one that was reclaimed in 1984 and a second that was reclaimed in <br />1988. Two reference areas (one in a big sagebrush shrubland type and one in a mixed grassland <br />type) were also sampled. Sampling results are presented for each of these areas. The reclaimed <br />areas were also sampled (for cover data) in 1989, 1990, 1991, 1992, 1993, 1994, 1995 and 1996. <br />Tabular summaries of mean cover data for the earlier sampling years are presented as a means of <br />evaluating vegetation changes that have occurred over the past nine growing seasons. Field <br />sampling for this project was conducted during August 1997. <br />METHODS <br />Samoling Locations. Random sampling locations were obtained by superimposing a grid <br />over a topographic map (1 inch = 200 feet) depicting the reclaimed areas. Grid cells (one-half inch <br />by one-half inch) in each of the reclaimed areas were numbered. Random numbers within the <br />ranges of the numbered cells were then drawn from a random numbers table. These cells then <br />became the sampling locations. Initially, 25 cells were selected. For certain measured parameters, <br />25 was an adequate number of samples. For other parameters, additional numbers were drawn <br />until sample adequacy was obtained. <br />Sampling locations in the reference areas were also randomly established. The reference <br />areas are essentially rectangular. Sampling sites were obtained using pairs of random coordinates. <br />Actual sites in the field were obtained by pacing distances from one wmer of the reference area. <br />Cover Data. Vegetation cover data were obtained using a point transact method. With <br />this approach, observations on plant cover were made at one-half meter intervals along a 25-meter <br />transact. At each observation point either in the reference areas or in the reclaimed areas, cover <br />was evaluated using an optical sighting device. The device consists of an objective lens equipped <br />with sighting cross-hairs, a focusing tube, and a reflecting mirror. The device was mounted on a <br />tripod and was oriented parallel to the ground at each observation point. The sighting device was <br />attached to a bar that is 0.5 meters in length. Observations were made by recording what was <br />observed at the point of intersection made by the cross-hairs. Two observations were made at each <br />half-meter along the transact (one on either side of the transact tape), for a total of 100 points per <br />transed. The number of samples in each area is shown in Table 1. <br />Table 1. S of sam le sizes. <br /> 1984 Reclaimed <br />Area 1988 Reclaimed Area Sagelxush <br />Refcrence Area Grassland <br />Refereocc Area <br />Cover Transacts 15 20 15 15 <br />Production Plots 55 20 15 19 <br />Densi Transacts 15 60 15 19 <br /> <br />