Effect of fire-induced cheatgrass invasion and land reclamation on ground dwelling arthropod populations. Gardner, Eric^*,1, Johnson, Robert ^*,, Anderson, Val ^*,, ¹ Integrative Biology, Provo, UT

ABSTRACT- The invasion of cheatgrass (Bromus tectorum) into western rangelands and the problems resulting from this invasion have prompted numerous efforts to reclaim areas infested with this weed. Reclamation of cheatgrass dominated rangelands traditionally incorporates desirable exotics rather than less competitive natives in seed mixes. Thus a native community may be changed by the invasion of cheatgrass, but remains altered from a natural community when replacing exotics with other exotics. This study examined the impact such changes in vegetation have on ground dwelling arthropod populations. Differences in abundance and diversity of ground dwelling arthropods in each of three states of rehabilitation were measured. These states represent a natural sagebrush(Artemisia tridentata) community, a community dominated by cheatgrass, and a reclaimed community consisting of desirable exotics mixed with native shrubs. Pitfall traps were used to collect arthropods during the summers of 2003 and 2004 in order to determine if the arthropod composition of the reclaimed community approximates a natural native condition or a cheatgrass dominated grassland.

KEY WORDS: Fire-Induced Cheatgrass