Abstract

GILL, STANTON. 1989. Cleaning up insects with insecticidal soap. Grounds Maintenance 24(7):34, 38.

In these days of heightened public concern about pesticide use, pesticide applicators are under more scrutany than ever before. The revival of insecticidal soap has resulted from this search for non-traditional methods of control. Insecticidal soap’s appeal comes from the selectivity of insects controlled and low mammalian toxicity of the material. Because insecticidal soaps control a narrower range of insects, they’re less likely to inadvertantly kill beneficial insects. This characteristic, as well as low persistence in the environment and low mammalian toxicity, make soap a promising tactic for use in integrated pest management programs. Various types of soaps have been used for insect suppression since the last half of the 19th century. Before 1940, researchers described the mode of action and efficacy of these soaps. Insecticidal soap is composed of potassium salts of several fatty acids. According to the popular theory, the fatty acids disrupt the pest’s cellular membrane which causes the loss of cellular contents and cell death. I tested the efficacy of insecticidal soap on azalea lace bug and the Eastern tent caterpillar. Timing was critical for lace bug control because you want to kill the nymph. The key to good caterpillar control was the ability of the sprayer to severely damage tents, thoroughly covering the caterpillars inside the webbed nest, as well as those on the branches and leaves.

• © 1990, International Society of Arboriculture. All rights reserved.