Canadian Forest Service Publications

Les forêts de la Côte Nord au Québec sont-elles sujettes aux déprédations par la tordeuse? 1983. Blais, J.R. The Forestry Chronicle 59 : 17-20.

Year: 1983

Issued by: Laurentian Forestry Centre

Catalog ID: 14352

Language: French

Availability: PDF (request by e-mail)

Mark record


Quebec's North Shore is a vast region comprising about one third of productive forests in the province. The impact of the spruce budworm (Choristoneura fumiferana (Clem.)) in this remote region was not well known. In the summer of 1981, ground and aerial surveys were conducted to determine the extent to which fir stands has been affected during the current budworm outbreak. It was possible to confirm that defoliation had been severe for several successive years prior to 1978, and that since then, insect populations had diminished considerably. Available information on balsam fir mortality indicated only two areas: one in Saguenay River region in the extreme southwest of the study area, and the other in the vicinity of Baie Comeau. The 1981 surveys revealed that varying quantities of fir had succumbed to budworm attack in many stands occurring for hundreds of kilometers east of Baie Comeau. The spruce budworm maintained high populations sufficiently long to cause pockets of tree mortality over a widespread area on the North Shore. Growth-ring measurements on several old balsam fir and white spruce trees from many localities indicated that no other widespread budworm outbreak had occurred on the North Shore since the end of the nineteenth century.