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• COVER Total vegetation cover on all reclaimed areas sampled in 1997 was significantly lower than in the 1996 sampling (Savage and Savage, 1996). In 1997, total vegetation cover on the Osgood Sand Reference Area exhibited a minor decrease of 0.9 percent from the 1996 cover values. In contrast, the 1985 Reclamation Area exhibited a 22.4 percent decrease from 1996, the 1986 Reclamation Area showed a 32.7 percent decrease from the 1996 cover values, and the 1987 Reclamation Area exhibited a 29.0 percent decrease in total cover from that sampled in 1996. The reclaimed area exhibiting the lowest vegetation cover during the 1997 sampling was the 1985 Reclamation Area with 24.20 percent total vegetative cover. The 1987 Reclamation Area exhibited the highest level of total vegetation cover with 26.80 percent. The total percent spread in cover for the three reclamation areas for 1997 was 2.60 percent, representing 10 percent of the mean value of the total cover from all reclaimed areas. The total vegetation cover on all reclaimed areas in 1997 was significantly less than that sampled within the Osgood Sand Reference Area in 1997. For this reason the 1985, 1986, and 1987 Reclamation Areas would not meet the final revegetation success criterion for cover if this comparison was based solely on the 1997 cover data. Figure 3 presents a comparison of total herbaceous cover from the Osgood Sand • Reference Area and the 1985, 1986, and 1987 Reclaimed Areas for the years 1994 through 1997. This data is plotted against January-July precipitation amounts. 1t is significant to note that the reclaimed areas always exhibit higher levels of herbaceous cover than the Osgood Sand Reference Area over all precipitation regimes. This indicates that differences in total vegetation cover between the reference area and the reclaimed areas is solely related to cover provided by woody plant species. Since the reclamation was designed to fulfill post-mining land uses which do not depend on woody shrubs, it may be prudent to re-examine the propriety of comparing a woody shrub dominated community with a warm season grassland, when discussing the success of revegetation at the Keenesburg Mine. HERBACEOUS PRODUCTION As with vegetation cover, herbaceous production from all areas during the 1997 growing season was significantly less than encountered in the 1995 sampling (production sampling was not undertaken in 1996, in accordance with sampling requirements for Phase I and II bond release). In 1997, herbaceous production on the Osgood Sand Reference Area was 81.6 percent less than herbaceous production in 1995. Similarly, herbaceous production at the 1985 Reclamation Area was 90.0 percent lower than 1995, and the 1986 and 1987 Reclamation Areas exhibited herbaceous production 79.0 percent and 84.0 percent less than their corresponding . areas in 1995. -14-