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• year) and a slight decrease in 1996, but appears to have rebounded during the last three years. 1995 Reclamation Areas Two years quantitative data exist for the 1995 reclamation areas, therefore insufficient data exists to evaluate long-term trends. However, the differences between the "normal" precipitation year of 1998 and the "wet" precipitation year 1999, aze appazent in the relative cover data. The following six species showed significant increases in relative cover from 1998; Agropyron cristatum (103.9%), Agropyron dasystachyum (432.3%), Bouteloua gracilis (143.3%), Bromus tectorum (235.6%), Calamovilja longiJolia (23.3%), and Helianthus annuus (14.0%). Seven additional species revealed significant decreases in relative cover this year. They included Agropyron intermedium (-87.8%), Agropyron smithii (-53.7%), Bromus marginatus (-43.9%), Oryzopsis hymenoides (-15.8%), Ambrosia psilostachya (-79.1%), Kochia scoparia (-79.0%), and Sisymbrium altissimum (-61.1%). SUMMARY Monitoring of the 1995 and 1997 reclamation areas, the 1998 reseeded or interseeded areas, and the Osgood sand reference area in 1999 showed that the 1995 and 1998 areas met final revegetation success criteria for total vegetation cover. The 1998 reseeded or • interseeded areas cover value mean was greater than 90 percent of the mean vegetation cover value from the Osgood sand reference area, and the mean from the 1995 reclamation areas was found to be statistically equivalent based on a Student's t test. With regard to total herbaceous production, the 1995 reclamation areas and the 1997 reclamation areas both exceeded the total herbaceous production value from the Osgood sand reference area, therefore meeting the revegetation success criterion for herbaceous production. A Student's t statistical test revealed that iota! herbaceous production from the 1998 reseeded or interseeded areas was sufficient to meet the revegetation success criterion for herbaceous production also. None of the areas sampled in 1999 could meet the species composition revegetation success criteria (including the Osgood sand reference azea). Based on the sampling conducted for vegetation cover, herbaceous production, and species composition in 1999, it was concluded that the 1995 reclamation areas have established a diverse, effective, and permanent vegetation cover of the same seasonal variety native to the area and are capable of self-regeneration and plant succession in accordance with the requirements of the Colorado Surface Coal Mining Reclamation Act. The 1997 and 1998 areas are developing diverse, permanent and effective vegetative communities. C~ -19-