Great Basin Naturalist


The population dynamics and decomposition activities of litter arthropods in an unmanaged sagehrush/bitterbrush habitat in southeastern Wyoming were assessed in 1986. The effects of sagebrush/bitterbrush management practices on litter arthropod communities and the role of these communities in decomposition were also assessed. Insecticide applications were used to selectively exclude arthropods in order to determine the ecological impact of these detritivores. Application of a herbicide, 2,4-D, was associated with increased arthropod populations for 30 days following treatment. Mowing increased arthropod densities at two different times, 10–30 days and 50 days post treatment, perhaps as a result of functional and numerical responses by litter arthropods. Elimination of arthropods from otherwise undisturbed shrub habitats by the use of broad-spectrum insecticides reduced the rate of litter decomposition during the growing season, indicating that these organisms play an important role in decomposition and nutrient cycling.