Abstract

Harper, J. D. 1974. Forest insect control with Bacillus thuringiensis: survey of current knowledge. Auburn University, Auburn, Alabama. 64 p.

Bacillus thuringiensis has been developed over the past two decades as a potent microbial insecticide. It is capable of rapidly reducing populations of certain actively feeding insects and preventing significant damage to their host food sources. A total of more than 150 insects, mostly lepidopterous larvae, are known to show some degree of susceptibility of “B.t.,”. It has been registered for use in the United States against more than 30 insect pests of agricultural, ornamental, and forest crops. Many of the world’s most important forest and shade tree resources are subject to attack by lepidopterous defoliators. In the past, most of these have been successfully controlled with synthetic chemical insecticides, notably the chlorinated hydrocarbons, among which, DDT was the most widely used. With greater public awareness of potential hazards associated with persistent chemical insecticides, and the resultant ban in the use of DDT and other persistent chlorinated hydrocarbons throughout much of the world, alternative methods of control were sought. B.t., because of its favorable characteristics of specificity, safety, biodegradability, and general efficacy against lepidopterous defoliators, was a natural choice for development by entomologists. The purpose of this report is to sort through as much of the experimental results as could be obtained from professional entomologists who have worked with the B.t.-forest insect interaction and to present an overall picture of the current status of B.t. as an alternative control method for various forest insect defoliators.

• © 1975, International Society of Arboriculture. All rights reserved.