Forty-six persons contributed to this review of aerial control technology, its implementation against forest insects in Canada from 1927 to 1973, and ensuing side effects on various components of the enviornment. Exploratory applications of calcium arsenate dust were made from aircraft over about 7,450 acres from 1927 to 1930. Owing to high unit costs, variable results and other factors, aerial dusting was abandoned as a means of coping with outbreaks of forest insects in this country. The first trials of aerial forest spraying took place in the mide-1940's, coincident with release of DDT and surplus military aircraft, and were soon followed by sizeable operational control programs. DDT was predominant among insecticides used in forestry operations until the late 1960's. Injury to fish and other forest fauna was experienced, despite progressively reduced dosage rates. The search for subsitutes, begun in the 1950's, led eventually to replacement of DDT by non-persistent organophosphates and carbamates in the late 1960's, with resulting elimination of injury to fish and sustantially reduced hazard to most other components of the environment.
