• Webb, F. E.
  Forest Biology Laboratory, Fredericton, N. B.
  
• Blais, J. R.
  Forest Biology Laboratory, Quebec, P. Q.
  
• Nash, R. W.
  State Entomologist, Maine Forest Service, Augusta, ME
  

The spruce budworm (Choristoneura fumiferana (Clem.)) is a forest pest in all Canadian Provinces and Territories, and in the northeastern, midwest, and northwestern United States. It is by far the most destructive insect affecting the extensive balsam fir-spruce forest types in Ontario Quebec, the Maritime Provinces, and Maine. Outbreaks of varying extent have been reported from these regions almost every year for the past half-century (deGryse, 1947). Periods in which outbreaks were particularly severe and widespread occurred from about 1909 to 1920 and in the 1940's and 1950's. In both periods, outbreaks showed a tendency to shift from west to east, intensifying first in parts of northern Ontario and Quebec and dying out in the Atlantic region south of the St. Lawrence River.

The main purpose of this paper is to place on record a cartographic history of the most recent spruce budworm out break in the Atlantic Region and of the spraying operations carried out from 1952 to 1958 in New Brunswick, in the Lower St. Lawrence-Gaspe areas of Quebec, and in northern Maine. Also Presented in support of the maps are synopses of data relating to outbreak history, operation statistics, and assessments of immediate results.