Tree Protection in Portland, ME

If you live in Portland or are thinking about moving there, tree protection are one of those things you probably won't think about until they affect you directly. Portland has 3 specific rules on the books covering different aspects of tree protection, and some of them might surprise you.

Heritage & Protected Trees

Portland's Heritage Tree Protection Ordinance bars removing a Heritage Tree, a privately owned tree in a designated historic district meeting size, species or Big Tree List criteria, without a permit from the City Arborist. The rule covers every qualifying tree citywide, not just street trees, and pairs removal with mandatory replacement or a Tree Trust payment.

Key details: Governing ordinance: Ord. No. 26-20/21, eff. 8-3-2020. Applies to: Heritage Trees, private property, historic districts. Permit authority: City Arborist / Parks, Rec. & Facilities Dept.. Review timeline: 21 calendar days (§ 29-10). Late-application window: 30 days after unpermitted removal (§ 29-11).

Removing a Heritage Tree without a permit does not excuse the owner from the permit process: § 29-11 requires the owner to apply for a Tree Permit within 30 days of the unpermitted removal, and every business day of continued noncompliance thereafter is a separate violation subject to the general penalty in § 1-15, a fine of $100 to $500 per offense, with each day a distinct offense. The Director of Parks, Recreation, and Facilities may issue a written stop-work order mailed to the property owner, and the city may seek injunctive relief in court against an ongoing violation.

This is one of the stricter rules in Portland's municipal code. If you are unsure whether your situation complies, it is worth checking with the city before proceeding.

Protected Tree Species

Portland's Heritage Tree Ordinance names the exact species and trunk-diameter thresholds that trigger protection: named shade trees at 24 inches DBH, ornamentals at 12 inches DBH, and specific rare native stands, all within a designated historic district on private land.

Key details: Oak/maple/etc. threshold: 24 inches DBH or greater. Ornamental species threshold: 12 inches DBH or greater. Rare native stands: Protected regardless of diameter. DBH measured at: 4.5 feet above ground (§ 29-3). Also protected: Any tree on Maine's Register of Big Trees.

The species list itself carries no independent penalty; it operates only to define which trees are subject to the § 29-5 removal-permit requirement. Removing a qualifying species at or above its listed DBH threshold without first obtaining a Heritage Tree Removal Permit triggers § 29-11 enforcement: the owner must apply within 30 days, each further day of noncompliance is a separate offense, and the general penalty of $100–$500 per offense under § 1-15 applies, alongside possible stop-work orders and injunctive relief.

Parkway Planting

Portland's Land Use Code requires every development subject to site plan review to plant one street tree for every 25 to 35 linear feet of frontage along a city right-of-way or private roadway, per the Technical Manual's landscaping standards. The review authority may approve an alternative only where site constraints genuinely block planting in the right-of-way. Removing an existing heritage or feature-mature street tree triggers a mandatory Tree Fund payment set above ordinary replacement cost.

Key details: Planting ratio: 1 street tree per 25-35 linear ft frontage. Reviewing body: Planning Authority / City Arborist. Alternative: Allowed only if site constraints proven. Heritage tree removal: Mandatory Tree Fund payment above cost. Effective: July 1, 2026 (Land Use Code).

There is no separate street-tree fine schedule; enforcement runs through site plan approval itself. The Planning Authority will not approve a plan that omits the required street-tree ratio or the City Arborist's recommended survival measures without an approved Technical Manual alternative. Removing a heritage or feature-mature street tree without qualifying for that alternative triggers a mandatory Tree Fund payment set well above ordinary tree-replacement cost, imposed as a condition of approval.

The Bottom Line

Portland's tree protection rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Portland is broadly strict or permissive.

All of the above reflects Portland's municipal code as of our last review. If you need specifics on fines, exemptions, or filing requirements, the detailed ordinance pages linked above have the full breakdown.