Spruce Budworm is Back in Maine
The spruce budworm is a moth native to the Northeast U.S. and proximate Canada’s spruce-fir forests. While always present in the landscape, the budworm had population surges on a 30-to-60-year interval. When this happens, the defoliation of fir and spruce can cause stand mortality.
The last significant Spruce Budworm outbreak in New England was from 1967 to 1993 and covered ~136 million acres across eastern Canada and Maine. Mortality rates for balsam fir reached 84-97%, and red spruce mortality reached 30-66%. This resulted in an estimated 20-25 million cords of spruce-fir, and hundreds of millions of lost revenue to the forest industry. Needless to say, the industry isn’t looking to repeat this event and is applying the lessons learned from that outbreak, as well as the experience gained in the past several years by our neighbors in Canada.
At a recent FRA Northeast Region Forest Forum, presenters from the Maine Forest Service and the state’s forest industry discussed the current Spruce Budworm outbreak in neighboring Quebec and New Brunswick, and the emergence of an outbreak in Northern Maine.
The map below shows recent outbreaks in Quebec, and it’s easy to see a cluster of activity up against the Maine border. (Note: the Province of Quebec produced this map, thus the French language labeling.)
Landowners across Northern New England have been using pheromone traps to monitor for the return of Spruce Budworm, and that work is – not surprisingly – now showing elevated levels of the insect in far Northern Maine, up against the Quebec border where an outbreak has occurred. The Spruce Budworm was clearly present at elevated levels in 2023, and this infestation grew in 2024.
If left unchecked, this outbreak threatens to spread and threatens Maine and Northern New England. An analysis prepared several years ago indicated that a severe outbreak could result in a reduced annual harvest of nearly 500,000 cords, an economic impact of about $800 million annually, and the loss of 3,800 jobs.
Maine, and the entire region, is looking to avoid this and is collaborating to execute a plan to limit the impact of this forest pest, focused on:
- Early Detection – Monitoring populations to detect hot spots;
- Early Intervention – Targeted insecticide treatment to prevent the spread; and
- Communication – Proactive communications and engagement with interested parties on project activities and results.
Maine landowners have been working with the state and federal government to fund this effort. To date, the federal government has committed $14 million to address the issue across Northern New England, with the vast majority heading to Maine. The State of Maine is expected to provide another $2 million, with private landowners funding the remainder of costs, as well as providing critical resources.
With this early intervention strategy, landowners and the state hope that they can suppress any outbreaks, providing a cooperative approach to a shared challenge.
Source for pictures: Maine Forest Service and cooperating partners
