• Suttman, Cheryl E
  Miami University
  
• Barret, Gary W.
  Miami University
  

The pesticide Sevin was applied to 4 of 8 0.1 ha plots of oats. These plots were left to normal ecological succession and the application process repeated during the old-field stage of succession. Arthropods in the oats field exhibited-greater decrease in  density and biomass than did arthropods in the old-field community following treatment. This response, however, was followed by a shorter recovery period than in the old-field community. The herbivorous arthropod response was usually immediate, pronounced, and short-term in duration, whereas the carnivorous response was normally delayed, less pronounced, and long-term in duration. Carnivorous Coleoptera were the most severely affected by pesticide treatment in both fields. Pesticide application produced a greater total effect on both species richness and species apportionment indices within the oats community as compelled to the old-field community. The old-field community appeared to show more resilience than the oats community. This resilience, however, cannot be accounted for by plant diversity'