Canadian Forest Service Publications

Year: 1963

Available from: Laurentian Forestry Centre

Catalog ID: 14933

Language: English

CFS Availability: PDF (request by e-mail)

Abstract

An attempt was made to suppress an incipient spruce budworm outbreak in the Lower St. Lawrence region of Quebec through the aerial application of DDT. Operations began in 1960 and continued in 1961 and 1962 when they finally met with success. Failure to achieve success earlier was due partly to the exceptionally favourable survival conditions for the insect in 1960, and partly to the inadvertent omission of a small infested area from the program in 1961. The operations greatly reduced spruce budworm populations each year in the outbreak area, while the action of natural control factors. including parasites and predators increased. The collapse of the outbreak was the result of the combined effects of the chemical treatments and of natural control factors.