The Effects of the Carbamate Insecticide Carbaryl upon Forest Soil Mites and Collembola1

Abstract

Test plots were established in a red-pine plantation and in a mixed hardwood stand on the Tully Forest, situated about 25 miles south of Syracuse, N. Y. Dosage rates varied from 0 to 50 lb per acre, and one treatment was with carbaryl and malathion combined. Neither mites nor Collembola were totally exterminated by any treatment used. The reduction in population was roughly proportional to the severity of the treatment up to a dosage of 10 lb per acre. The 50-lb-per-acre treatment had little additional effect. The rate of population increase of the mites 4-5 months after treatment was directly proportional to the dosage applied; i.e., greatest where the treatment was heaviest. The population of mites was far greater on treated plots than on the controls at the close of this experiment. Collembola are more sensitive to treatment than mites, and do not recover so rapidly.