From mid-July into August, you may see swarms of Spruce Budworm moths flying near your house. This is a common occurrence during budworm outbreaks and usually reflects the ‘perfect storm’ of favorable weather conditions (i.e., warm and windy weather) mixed with the mass emergence of budworm moths as they emerge from the cocoon stage.

Why do they disperse?

Spruce budworm moths disperse to find new areas where they can lay their eggs. These eggs can appear on foliage in bright green masses, and when they hatch, introduce a new generation of budworm to new areas throughout the region. While we know that there is a lot of dispersal that takes place during a budworm outbreak, it remains unclear how important these dispersal events are for spreading the outbreak.

In eastern Canada, researchers with the Healthy Forest Partnership spend a considerable amount of effort trying to track moth dispersal. Using moths collected from different provinces and locations, researchers hope to learn more about the condition of the moths that are dispersing throughout the province and whether they are a likely source of outbreak spread.

What can I do to help?

Look for moths (live or dead) beneath your porch or street light. They may be on the ground or wall.
Sweep these moths into a paper or plastic bag.
Add a piece of paper that has your name, address (of collection), and the date.
Put the bag into your freezer (this is important to preserve the eggs for counting).
Repeat a few time a week, if possible.
Contact us and we’ll arrange pickup of moths.
Contact Emily Owens (Budworm Tracker Coordinator) via

E-mail (
Twitter (@emilyowenz)
Facebook ( or
The Website (