Some Phases of the Japanese Beetle Insecticide Investigations1

Abstract

Effective measures for the protection of many economic plants from injury by the Japanese beetle (Popillia japonica ) have resulted from insecticide investigations. Various factors influencing the results of insecticide experiments are discussed. Data are given to show that certain non-toxic materials are as effective in repelling beetles as lead arsenate, indicating that other factors besides toxicity are responsible for the repellence of the lead arsenate sprays. The great difficulty in obtaining a high mortality of beetles with a stomach poison has been, first, to get the beetles to come to poisoned foliage, and, second, to get them to eat the poison. Progress in this connection is reported, together with methods for killing beetles otherwise than by the use of a stomach poison. In cases of heavy infestation there is some doubt whether a large percentage of kill and a high degree of protection can be obtained by means of a stomach insecticide.