Outbreaks of eastern spruce budworm occur regularly in the boreal, Great Lakes and Acadian forest regions of Canada. As natural disturbances, they are an integral part of these forest ecosystems. Nevertheless, the spruce budworm is one of the most damaging native insects affecting spruces and true fir in Canada. During a major outbreak, tens of millions of hectares of trees can be severely defoliated by the insect. An outbreak may last several years, and cumulative defoliation can cause significant levels of mortality and growth loss in mature softwood forests. This in turn can result in significant losses of important timber and non-timber resources, negatively affecting the forest industry and forestry-dependent communities.
For an accessible version:
http://www.nrcan.gc.ca/science/video/18354
