Robert Bryan is a licensed forester from Harpswell and author or co-author of numerous publications on managing forests for wildlife. Paul Larrivee is a licensed forester from New Gloucester who manages both private and public lands, and a former Maine Forest Service forester.
In November 2025, the Department of Environmental Protection (DEP) approved a conservation plan and forest management plan as mitigation for impacts from the NECEC transmission corridor that runs from the Quebec border 53 miles to central Maine.
As professional foresters, we were astonished by the lack of scientific credibility in the definition of “mature forest habitat” that was approved by DEP, and the business-as-usual commercial forestry proposed for over 80% of the conservation area.
The DEP’s approval requires NECEC to establish and protect 50,000 acres to be managed for mature-forest wildlife species and wildlife travel corridors along riparian areas and between mature forest habitats. The conservation plan will establish an area adjacent to the new transmission corridor to be protected under a conservation easement held by the state. Under this plan, 50% of the area will be managed as mature forest habitat.
Under the forest management plan, a typical even-aged stand will qualify as “mature forest habitat” once 50 feet tall, which is only about 50 years old. These stands will lack large trees that provide wildlife denning and nesting sites, multiple vegetation layers that mature-forest birds use for nesting and feeding habitats and large decaying trees and downed logs that provide habitat for insects, fungi and small mammals, which in turn benefit larger predators.
Another major concern is that contrary to the earlier DEP order, the final approval allows standard sustainable forestry operations on the 84% of the forest located outside the stream buffers and special habitats. These stands may be harvested as soon as they achieve the “mature forest habitat” definition, as long as 50% of the conserved land is maintained as “mature.”
After the mature forest goal is reached, clearcutting or other heavy harvesting could occur on thousands of acres every 10 years. Because the landowner — Weyerhaeuser — owns several hundred thousand acres in the vicinity, any reductions in harvesting within the conservation area can simply be offset by cutting more heavily nearby. As a result, the net
mature-forest benefit of the conservation area will be close to zero.
Third, because some mature stands will be cut before the 50% mature forest goal is reached, it will take 40 years — longer than necessary — to reach the goal.
In the near future the Board of Environmental Protection (BEP) will consider an appeal from environmental organizations of the plan approval. To ensure that ecologically mature forest develops in a manner that meets the intent of the DEP/BEP orders, several things need to change.
First and most important, to ensure that characteristics of mature forest habitat have time to develop it is critical that the definition include clear requirements for the minimum number of large-diameter (hence more mature) trees, adjusted by forest type. At least half the stocking of an area of mature forest habitat should be in trees at least 10 inches in diameter, and at least 20% of stands beyond the riparian buffers should have half the stocking in trees greater than or equal to 16 inches in diameter.
Current research as well as guidelines for defining ecologically mature forests, such as those in Maine Audubon’s Forestry for Maine Birds, should be followed.
Second, limits should be placed on the size and distribution of clearcut or “shelterwood” harvest patches so that even-aged harvests are similar in size to those created by typical natural forest disturbance patterns. These changes will help ensure that the mature-forest block and connectivity requirements of the orders are met.
Third, because the forest impacts have already occurred, no cutting should be allowed in the few stands that meet or exceed the DEP-approved definition — which needs to be revised as described above — until the 50% or greater mature-forest goal is reached.
If allowed to stand, the definitions and management described in the forest management plan would set a terrible precedent for conserving mature forests in Maine. The BEP should uphold the appeal and establish standards for truly mature forest habitat.