THE EFFECTS OF SUMITHION AND PHOSPHAMIDON ON POPULATIONS OF FIVE CARABID BEETLES AND THE SPIDERTROCHOSA TERRICOLAIN NORTHWESTERN ONTARIO AND INCLUDING A LIST OF COLLECTED SPECIES OF CARABID BEETLES AND SPIDERS

Abstract

In an attempt to control the spruce budworm in northwestern Ontario, Sumithion and Phosphamidon were sprayed from the air in June 1968. Some carabid beetles and one spider were studied to assess the effect the insecticides had on forest floor arthropods in mixed boreal forest. A sudden decrease in collected specimens both in and out of the spray area 1 week prior to spraying was probably due to reduced activity caused by heavy rainfall, but during and following the spray period there were fewer specimens collected in the spray area than in the control area.