Portland, ME Tree Protection: Protected Tree Species (2026)
Key Facts
- 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
Summary
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.
2. Certain trees 24 inches in diameter or greater (diameter at breast height or DBH): Oak species including White Oak, Red Oak, Pin Oak, Swamp White Oak, and Burr Oak; Sugar Maple and Red Maple; Shagbark Hickory; Ginkgo; Tulip Poplar; Cucumber Magnolia; Elm; Birch species; Hemlock; Pine; Spruce; Horse Chestnut; Walnut; Catalpa; Black Cherry; Linden; Sweetgum; European Beech; Honey Locust; and Sycamore; and 3. Ornamental trees 12 inches in diameter or greater (DBH) including Dogwood, Magnolia, Dawn Redwood, Japanese Maple, Hawthorn, Apple, Chameacyparis, Cherry, Hornbeam, Amelanchier, Sassafras, and Mulberry.
Official source re-checked September 7, 2026: the cited page had not changed since it was quoted.
Full Breakdown
Section 29-3 of the Portland Code of Ordinances defines "Heritage Tree" with a species-by-species list that determines which trees actually fall under the removal-permit requirement of § 29-5. " A fourth category protects "Stands of native trees that are rare or threatened including Shagbark Hickory, Pitch Pine, American Mountain Ash, Red Spruce, and Atlantic White Cedar" regardless of individual diameter. DBH is measured under § 29-3 at four and a half feet above the ground, and for a multi-trunk tree the DBH is the aggregate diameter of all trunks.
A tree that meets none of these species/size criteria and is not on the Big Tree List is not a Heritage Tree and is not subject to the ordinance's permit or replacement requirements, regardless of its age or location.
Violations & Fines
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.
Frequently Asked Questions
Which tree species are protected under Portland's Heritage Tree Ordinance?
Does a small oak tree count as a Heritage Tree in Portland?
Is a Japanese Maple protected the same as an oak in Portland?
Sources & Official References
Other rules in Portland
Compare Portland to another location·View the Maine tree protection overview
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