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• or introduced." A comparison of the 1999 species composition data with the revegetation success standazd reveals that none of the reclaimed areas sampled in 1999, or the Osgood sand reference area, would meet the final bond release species composition success standard. Species presence and representation on the reclaimed areas was greater than encountered in 1998 (Table 12). The Osgood sand reference area contained one more species in 1999 than in 1998, while the 1995 reclamation areas increased in species numbers from 19 (1998) to 22 this yeaz. COMPARISON OF VEGETATION COMMUNITIES: 1994-1999 Comparisons of 1999 monitoring data with previous years can only be undertaken for the Osgood sand reference area and the 1995 reclamation areas. Savage and Savage has been monitoring the Osgood sand reference area and [he 1985, 1986, and ]987 reclamation areas since 1994 (Savage and Savage, 1994, 1995, 1996, 1997, 1998). Monitoring of the 1985, 1986, and 1987 reclamation areas was not undertaken this year, based on their success in prior years. The 1995 reclamation areas were initially monitored in 1998. Initial quantitative monitoring of the 1997 reclamation areas and 1998 reseeded or interseeded areas began this year. • Table ]2 presents comparisons of relative cover for encountered plant species within the Osgood sand reference area and the 1985, 1986, 1987, 1995, 1997, and 1998 reclaimed areas for the years 1994-1999. Though some of the areas were not monitored quantitatively this yeaz, the data is presented for historical and developmental comparison purposes. Within the table are several interesting trends revealing changes in species composition at the reference and reclaimed areas. Osgood Sand Reference Area Last year (Savage and Savage, 1998) it was noted that Stipa viridula had consistently increased over the five prior years. This year, the relative cover of Stipa viridula dropped by over 45 percent from 1998. This appears to be in contradiction to increased spring precipitation that should benefit this species. Bouteloua gracilis, which had decreased in relative cover in 1998 after increasing in the previous years, has shown an increase in the 1999 sampling. Andropogon hallii and Ca/omovilja longijolia appear to have responded to precipitation trends, increasing with wet years, decreasing with the drier years, and showing an increase in 1999 again with a more mesic precipitation regime. Helianthus annuu.s appears to be opportunistic in growth, and appears to have responded rapidly to the early season precipitation. This native annual appears in the normal and wet precipitation years but not in drier years. The same could be said for Bromus tectorum, which increased 259.5 percent from 1998. The invasion of Bromus tectorum in the reference azea bears further inspection, based on dominance of the species in the adjacent • range. Artemi.sia filijolia showed a significant decrease in relative cover in 1995 (a wet -18-