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three yeazs, decreased slightly in 2001, and increased significantly this yeaz. Bromus <br />tectorum relative cover decreased significantly this season, again revealing its sensitivity to <br />• spring precipitation. Neither Ambrosia psilostachya or Helianthus annuus were <br />encountered in the sampling in the 1995 reclamation azeas this yeaz, likely due to the <br />significant drought conditions. <br />1997 Reclamation Areas <br />Quantitative sampling has been undertaken in this azea for the past four growing seasons. <br />During this time thirty-two species have been encountered. Of those species, seven have <br />been present in all yeazs. These species include one perennial warm season grass <br />(Calamovilfa longifolia), one perennial cool season grass (Oryzopsis hymenoides), one <br />annual grass (Bromus tectorum), one perennial native forb (Ambrosia psilostachya), one <br />biennial forb (Melilotus o~cirralis), one native annual forb (Helianthus annuus), and one <br />introduced annual forb (Kochia scoparia). <br />In the 1997 reclamation areas this yeaz, the warm season Calamovilfa longifolia increased <br />slightly in relative cover, cool season Oryzopsis hymenoides increased slightly, and the <br />cool season annual Bromus tectorum decreased 80 percent. Ambrosia psilostachya <br />decreased significantly in 2002 (91%), as did Melilotus officinalis (77%). Helianthus <br />annuus decreased 34 percent this dry yeaz, while Kochia scoparia increased 1892 percent. <br />These changes reflect the significance of the drought conditions on both relative cover and <br />species composition. <br />• 1998 Reseeded or Interseeded Areas <br />Quantitative sampling has been undertaken in these areas for the past four growing <br />seasons. During this time thirty species have been encountered. Of the species <br />encountered, eleven have been present all years. These species include four perennial <br />warm season grasses (Andropogon hallii, Bouteloua curtipendula, Bouteloua gracilis, <br />and Calamovilfa longifolia), three perennial cool season grasses (Agropyron smithii, <br />Oryzopsis hymenoides, and Stipa viridula), one annual grass (Bromus tectorum), one <br />perennial native forb (Ambrosia psilostachya), one native annual forb (Helianthus <br />annuus), and one introduced annual forb (Kochia scoparia). <br />Of the species present in all yeazs, only Agropyron smithii has consistently increased in <br />relative cover. Andropogon hatlii, Bouteloua curtipendula, and Calamovilfa longifolia, <br />all warm season graminoids, and Stipa viridula, a cool season grass, have greater relative <br />cover during dry conditions. Bouteloua gracilis relative cover is not directly correlated <br />with precipitation, while Bromus tectorum growth is. Ambrosia psilostachya decreased in <br />relative cover for the first time this season. Until this yeaz, this species appeared <br />unaffected by drought conditions. Kochia scoparia and Helianthus annuus aze <br />opportunistic forbs responding to precipitation or the opening of space in burned azeas. <br />I • <br />CooreEnergyCompary Page 20 <br />2002 Revegetation Monitoring ReporC <br />