Tree and shrub services in Biddeford, Maine.

The Maine Forest Service lists Biddeford inside four forest pest quarantines: emerald ash borer, hemlock woolly adelgid, white pine blister rust and spongy moth. Each points to a different watch list. Ash trees are monitored for the thinning crowns and D-shaped exit holes of the borer; hemlocks are checked on the undersides of branches for the white woolly masses of the adelgid; white pines are checked for blister rust cankers, spread by nearby currants and gooseberries; and oaks are watched for spongy moth defoliation in outbreak years.

In 2026 the state proposed repealing its emerald ash borer quarantine, which would change firewood and wood-movement rules, not the threat to ash trees themselves.

On lots within 250 feet of tidal water, the state's shoreland guidelines keep a vegetated buffer closest to the shore. Selective pruning that maintains a well-distributed stand is allowed there, but cutting that opens views or creates gaps larger than 250 square feet is not. The code enforcement officer can ask for an evaluation from a licensed arborist before a hazard tree in that zone is removed.

Along the Saco, the river corridor adds another layer. The Saco River Corridor Commission regulates land within 500 feet of the river, or up to 1,000 feet across a wide floodplain, and Biddeford has close to 15 miles of that frontage. Routine pruning that keeps a tree healthy fits easily within those rules; heavier cutting on a riverbank is checked with the Commission first, and that check is part of how an arborist's recommendation is written.