• Blais, J.R
  
• Martineau, R.
  

The main topics discussed in this paper are: the progress of the spruce budworm outbreak in the Lower St. Lawrence- Gaspe regions from 1949 to 1956; the areas sprayed between 1954 and 1958 ; timing of spray application in relation to insect abundance and development; effects of treatment on spruce budworm population and on defoliation of balsam fir; results of aerial defoliation surveys and egg surveys; estimated amounts of wood destroyed by the insect, and losses averted through spraying; the various natural control factors associated with the decline and the eventual collapse of the outbreak.