A 5-Year Report of Observations in the Japanese Beetle Control Area at Sheldon, Illinois

Abstract

Beginning in the spring of 1954 and continuing through 1958, dieldrin was applied by the Division of Plant Pest Control Agricultural Research Service, U. S. Department of Agriculture, and the Illinois Department of Agriculture for suppression of a local infestation of Japanese beetles ( Popillia japonica New.) near Sheldon, Illinois. During this 5-year period dieldrin was broadcast over 17,844 acres of Illinois farm land at a dosage of 2 or 3 pounds of toxicant per acre. Records were obtained on the effects of the treatment on the Japanese beetle, other insects, earthworms, and livestock. One treatment of dieldrin gave excellent control of Japanese beetle larvae during the 5 years covered by this study. Many other insects that come in occasional or frequent contact with the treated soil were controlled for periods ranging from 1 to 5 years. Populations of a few economic insects increased following the treatments of dieldrin, but the increase was not great enough to warrant additional control measures. Some predators were adversely affected or eliminated by the dieldrin, whereas other predators and parasites appeared not to be harmed. The treatment did not eliminate earthworms. Farm livestock confined to pastures or farm lots treated by airplane with 20 or 30 pounds of 10% granulated dieldrin per acre showed no ill effects. However, poisoning and death oecurred in livestock, particularly sheep, exposed to drift from aerial sprays of 3 pounds of dieldrin per acre. The magnitude of dieldrin residues found on forage treated with granulated dieldrin depended to a considerable extent on the condition of the forage at the time it was treated.