• Dimond, John B.
  University of Maine
  
• Kittredge, Mark
  University of Maine
  
• Schaufler, Douglas
  University of Maine
  
• Pratt, Daniel
  Maine Forest Service
  

In May 1978, Bacillus thuringiensis, formulated as Thuricide 16B, was applied operationally for the first time against spruce budworm in Maine. This operation was a part of the 1978 Maine Cooperative Spruce Budworm Suppression Project, a cooperative undertaking of the Maine Forest Service, the USDA Forest Service, and the state's forest land-owners. The planning for this project was based on a series of past experimental trials in Maine going back to 1963 (Morrison and Dimond, 1978, p. 3) and an experience in Canada.

Efficacy studies were conducted by Prof. John Dimond, Dept. of Entomology, UMO. In terms of foliage protection, the operation was successful. Larval mortality was 81% in the treated area compared to 72% in the unsprayed controls, and survivors were smaller and retarded in development compared to the untreated area.

In cooperation with the Department of Agricultural Engineering at UMO, an evaluation of the mixing system was obtained and meteorological measurements taken.

Additional analysis will be performed using data gathered in this project.

Mixtures of "BT" with sublethal doses of chemical insecticides have been successfully used elsewhere (Morris, 1977a, 1977b), but this program used "BT" with no additives of any kind.