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• significant results in each case. This analysis confirms the assertion that the shrub <br />dominated reference area behaves differently than the graminoid communities of the <br />reclaimed mine site. The vegetation cover of the reference area is not as closely tied to <br />the precipitation regime of the area as is the graminoid community of the reclaimed <br />mine site. This illustrates a significant difference between the reference area and the <br />reclaimed areas, and begs the question of the propriety of comparing them in terms of <br />determining revegetation success. <br />An analogous analysis of the Osgood Sand Reference Area and the ]985, 1986, and <br />1987 Reclaimed Areas was undertaken using total herbaceous production data from <br />1994 through 1997. 1'he results of the statistical analysis were the same as those of the <br />vegetation cover analysis. Total herbaceous production and January-July precipitation <br />were not statistically significantly correlated in the Osgood Sand Reference Area. <br />Within the reclaimed areas, tots] herbaceous production and January-July precipitation <br />were significantly correlated, again indicating a significant difference between the <br />reference azea and the reclaimed areas. <br />Table 12 presents comparisons of relative cover for encountered plant species within <br />the Osgood Sand Reference Area and the 1985, 1986, and 1987 Reclaimed Areas for <br />the years 1994-1997. Within the table are several interesting trends revealing changes <br />in species composition at the reference and reclaimed azeas. <br />• Within the Osgood Sand Reference Area the most significant trend is the increase in <br />Bouteloua gracilis and Stipa viridula over the last four years. Andropogon hallii and <br />Calamovilfa /ongifolia appear to have responded to precipitation trends, increasing with <br />the wet year and decreasing with the drier years. Erigeron be/lidiastrum has shown a <br />significant decrease in relative wver over the last three years. Artemesia 61i1o/ia <br />showed a significant decrease in 1995 (a wet yeaz) and a slight decrease in 1996, but <br />appeazs to have rebounded in 1997. <br />The 1485 Reclamation Area showed several strong trends over the last four years. <br />Two cool season grasses, ~gropyron cristatum and Bromus marginatus have shown <br />significant decreases in relative cover, illustrating their short-lived nature in this biome <br />dominated by warm season graminoids. Bouteloua gracilis and Andropogon hallii, <br />both warm season grasses, have shown significant increases in relative cover over the <br />same time period, as has the native forb, Ambrosia psilostach}a. Calamovilla <br />longifolia has remained consistently successful in all of the reclaimed azeas over the last <br />four years. <br />The 1986 Reclaimed Area did not reveal any significant trends related to species <br />composition over the years 1994 through 1997. <br />Species composition trends in the 1987 Reclamation Area reflect those discussed for the <br />• 1985 Reclamation Area. Bouteloua gracilis shows increasing representation in the <br />community. Interestingly, Bromus marginatus, a cool season grass, also shows <br />-17- <br />