One small insect could shape the future of Maine’s forest economy: the spruce budworm. The eastern spruce budworm (Choristoneura fumiferana) is a moth native to Maine whose caterpillar stage can severely damage balsam fir and spruce trees. Outbreaks have been a consistent issue in the state, usually occurring every The caterpillars feed on the trees’ needles, causing defoliation. Repeated severe defoliation can reduce growth and eventually kill trees.. Outbreaks can have detrimental effects on Maine’s forest economy, making strategic planning necessary to mitigate future harm.
At the University of Maine, researchers are looking at the full scope of the spruce budworm’s potential effects by conducting targeted economic analysis that builds on the work of the 2016 spruce budworm task force. The task force examined potential effects on wood supply and harvesting, as well as pre-salvage and salvage planning and markets for affected timber. This summer, Wellesley College undergraduate Madeline Pierce explored the relationship between high-risk forests and Maine’s sawmills, pulp mills and biomass facilities through the NSF EPSCoR Maine-FOREST Summer Research Experiences for Undergraduates) (REU) program. Working with Adam Daigneault, Jianheng Zhao and Naresh Khanal in 91’s Forest Policy and Economics Lab, she mapped estimated procurement zones: areas from which mills could potentially obtain wood under the model’s economic assumptions.
“What we really want to look at is the trees that might be vulnerable in the future, and what mills, specifically, are those trees going to impact? So by looking at an estimated procurement zone of where these mills potentially could be getting their wood from, we will know which areas are more vulnerable and should have earlier intervention,” said Pierce.
Tackling the spruce budworm problem from both economic and biological perspectives, Pierce’s project seeks to identify areas where trees will be most affected and whether wood from those areas can successfully be procured before damage occurs. To do this, Pierce collected data on forest composition, mill locations, trucking routes, road networks and overall land constraints to map procurement zones and susceptibility of hosting spruce budworms.
Her preliminary results show that the potential for successful procurement varies by region. Areas in southeastern and eastern Maine with high spruce budworm vulnerability generally fall within procurement zones, while areas in northwestern Maine fall outside them. The findings suggest that biological risk could be coupled with economic vulnerability in northwestern Maine.
For Pierce, insect damage to forests is not a novel concept. A Colorado native, she has seen firsthand the effects of the mountain pine beetle, an insect that can be highly destructive to the region’s pine trees.
“It was really interesting to compare this research to my experience growing up in Colorado and seeing the damage done to trees, but then seeing how different the situation in Maine is when you factor in the forest economy, connection to Canadian forestry and different dynamics overall,” said Pierce.
For Pierce, the summer also represented the chance to go beyond theoretical work and apply economic research in a real-world setting.
“I really enjoy theory work but there can be limitations to how well you can apply it. I’m really excited I got the opportunity to expand my knowledge this summer and can now take this experience to better approach empirical projects. Having both sides will be highly beneficial in my future career development,” said Pierce.
As spruce budworm threatens forests across the state, understanding where its biological and economic effects may be greatest can help Maine prepare for the outsized consequences of one small insect.
Story by Heather Johnson, EPSCoR Graduate Assistant
