Credit: USDA Forest Service, Region 6, State and Private Forestry, Forest Health Protection. Collection: Region 6, Forest Health Protection historical files located at the Mt. Hood National Forest in Sandy, Oregon. US Forest Service image reference: 513670
Note: "During the period of June 10 to July 1 , 1965, a total of 65,945 acres were sprayed with DDT for control of early-instar larvae (Perkins and Dolph 1967). Application was by helicopter and at the rate of 0. 75 pound DDT in 1 gallon of fuel oil formulation per acre. Because of public concern at this time about side effects of DDT in the environment, impact of the spray on other resources, including fish, water, soil, forage, and cattle, was evaluated by scientists working independently of the project (Crouch and Perkins 1968, Tarrant et al. 1972). In addition, a small test was made of two other candidate insecticides, Dursban, an organic phosphate, and Zectran, a carbamate." From: Wickman, B.E.; R.R. Mason; and C.G. Thompson. 1973. Major Outbreaks of the Douglas-fir Tussock Moth in Oregon and California. GTR-PNW-5. USDA Forest Service, Pacific Northwest Forest and Range Experiment Station. 18 p. www.fs.fed.us/pnw/pubs/pnw_gtr005.pdf
See also: Crouch, G. L., and R, F. Perkins. 1968, Surveillance report, 1965 Burns Project, Douglas-fir tussock moth control. Malheur and Ochoco National Forests. USDA Forest Service. Pacific Northwest Region, Insect and Disease Control Branch, Division of Timber Management. 20 p.