Spruce Budworm: An Early Intervention Strategy




The spruce budworm poses a threat to forests and forest industries in eastern North America. The last extensive outbreak damaged more than 50 million hectares in the 1970s and 1980s.Today, an outbreak is occurring in Quebec, and budworm populations are on the rise in New Brunswick.

Natural Resources Canada's scientists have been studying the budworm for decades. In an unprecedented collaboration, scientists, governments, academics and stakeholders in eastern Canada and the U.S. have formed the "Healthy Forest Partnership" to proactively treat and protect the forest from spruce budworm damage.

Dr. Dave MacLean:

The spruce budworm outbreaks are a really important part of forests in eastern Canada when major outbreaks happen, and we're really trying to get ahead of that with the early intervention strategy, and that's why we've mobilized this strong team of industry, academics and government to work together to try to find a new approach to prevent the large scale epidemics.

Results from Quebec over the last few years have shown that when budworm is at really low population levels the males have a hard time finding the females and mating success is low. So the idea behind the early intervention strategy is to identify hot spots through really intensive monitoring of the forest to find places where the budworm is starting to rise and then go in and use the tools that we have to intervene early and try to drive the budworm population back down to these low levels.


Researchers are currently testing new treatment options and technologies that may give forest managers a bigger "tool box" to use in fighting budworm infestations.

Dr. Rob Johns:

This is a new approach to managing spruce budworm outbreaks where we're essentially controlling hot spots along the leading edge of the outbreak. We're hoping this is going to slow or perhaps prevent the spread of the outbreak.

Although results are still preliminary, we've had fairly good success controlling populations, locally at least, along the leading edge of the outbreak.


Scientists also believe that one of the keys to combatting budworm outbreaks is through the use of pheromones.

Dr. Peter Silk:

Pheromones are naturally produced behaviour modifying chemicals that synthetically they can be put into traps to lure insects and detect them and also to disrupt their mating processes. It's registered for use against the spruce budworm, we're developing that technique as an environmentally benign way of controlling insect populations at very low densities.

Budworm right now is at low densities and here's our opportunity, once in a lifetime opportunity, to test this technology against the budworm.


Part of the Early Intervention Strategy also aims to gain greater understanding of the spruce budworm, how it lives, its predators, how it copes and survives in the forest.

Kate Van Rooyen:

Natural Resources Canada is using DNA bar coding to help identify the organisms in the spruce budworm food complex. This allows us to understand who is who, who is eating who and how those different insects are interacting with each other. As a bigger picture, this allows us to understand all the participants in the food web which allows us to create better management options for the spruce budworm.


NRCan scientists and our many partners will continue to research innovative solutions to the spruce budworm epidemic in Eastern Canada.

For more information and updates, please visit healthyforestpartnership.ca.