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• revegetated communities, the native communities are old, and represent later stages in <br />vegetation community development. <br />Therein lies the conundrum. Is it reasonable to expect comparability between these two <br />disparate types of vegetation communities? Rickliefs (1973) reports the results of <br />vegetation community successional studies as particularly variable, with researchers <br />reporting climax stage development ranging from twenty to forty years for Colorado <br />eastern plains grasslands (Shantz, 1917) and 150 yeazs for a forest climax {Oosting 1942). <br />A complete successional sequence from barren sand to climax forest (a primary <br />successional sequence) may require a millennium (Olson, 1958). <br />Pre-disturbance vegetation at the Keenesburg Mine consisted largely of a shrub <br />community dominated by sand sage (Artemisia filifolia). The dominance of this shrub is <br />likely due to the long history of range grazing, the porous nature of the aeolian sandy <br />soils, and the low level of annual precipitation (13 inches). The Osgood sand reference <br />area is dominated by Artemisia filifolia with contributions by Stipa viridula, Calamovilfa <br />longifolia, Andropogon lwllii, and Bouteloua gracilis. <br />Since 1994, annual monitoring of the reference area and revegetated areas has been <br />conducted (Savage and Savage 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001). <br />Quantitative observations of the revegetated areas reveal continued development of a <br />warm season gaminoid prairie community. Reference area observations over the same <br />• period reveal ashrub-dominated community with low diversity. Using quantitative data <br />from the sampling of the reference azea and revegetated azeas in 2001 (Tables 1-4) the <br />differences in the composition of the vegetation cover in the areas are revealed. The shrub <br />Artemisia frlifolia dominates the reference area with 54 percent of the relative vegetation <br />cover. Graminoids in the reference area account for approximately one-third of the <br />relative cover while forbs account for nine percent. Within the revegetated azeas <br />graminoids dominate (56.91-86.10% relative wver), with less significant contributions by <br />forbs (10.88-41.46% relative cover), succulents (0%), and shrubs (0.32-3.02%) <br />(Tables 2-4). The revegetated areas also contain greater numbers of species, particularly <br />graminoids and forbs (Table 5). Herbaceous production remains greater on the <br />revegetated areas, largely due to the absence of competition from Artemisia (Table 6). <br />Similar observations have been made over the entire period of record (1994-2001). The <br />dominant lifeforms of the reference area and the reclaimed areas differ as does the species <br />composition. The design and implementation of the approved revegetation plan and the <br />successful results of the plan indicate that the reference area and reclaimed areas will not <br />develop similar vegetation communities, though the reclaimed areas aze successful, as <br />determined by sampling and bond release criteria. Therefore, it is recommended that <br />several steps be taken to acknowledge the distinct differences between the reference and <br />reclaimed areas and modify the revegetation success criteria accordingly. <br />-3- <br />