What changed on March 1, 2024
Newton’s updated Tree Preservation Ordinance became effective on March 1, 2024. The most important practical change for project teams is that the protected-tree threshold now starts at 6 inches DBH, not 8 inches. That means far more trees are captured during additions, demolitions, and site redevelopment.
Tree Save Area rules
- Newton defines the Tree Save Area as the area within the drip line of the tree, or a radius of 1.5 feet for every 1 inch of DBH, whichever is greater.
- Construction activity inside that Tree Save Area is prohibited unless it is authorized through an approved tree permit and Tree Protection Plan.
- The restriction applies not only to trees on the subject lot, but also to protected trees on adjoining lots when their Tree Save Area crosses the property line.
Exempt versus non-exempt removals
- Dead, diseased, or hazardous trees can be exempt from replacement, but Newton still expects a permit record and arborist support.
- On an owner-occupied one- or two-family lot, a healthy tree under 40 inches DBH can be exempt from replacement and payment if there is no construction permit within 24 months.
- That owner-occupied exemption is narrow. If construction arrives within 24 months, Newton can trigger retroactive replacement or payment.
Replacement burden
- For removals from 6 to 24 inches DBH, required replacement inches generally track the removed diameter one-for-one.
- At 25 inches DBH, the replacement requirement increases to 1.5x the removed diameter.
- At 40 inches DBH, the replacement requirement increases to 2x the removed diameter.
- At 56 inches DBH, the replacement requirement increases to 3x the removed diameter.
- Newton also publishes a payment-in-lieu table. The workbook-backed calculator on this page follows that table through 56 inches DBH. For 57 inches and above, the internal tool routes the applicant to the Tree Warden.
What municipalities typically expect in a submittal
- A tree inventory identifying DBH, species, and condition for protected trees on the site and, where relevant, along affected lot lines.
- A Tree Protection Plan showing fencing, no-disturb zones, trenching strategy, root pruning, air-spading, and monitoring notes.
- Clear documentation of how excavation, grading, utilities, staging, and access routes avoid or mitigate impacts inside the Tree Save Area.
- A replacement or payment-in-lieu strategy if removals are proposed.
Where projects get stuck
Teams usually lose time in Newton when the site plan reaches review before anyone has quantified the protected trees, accounted for adjoining-lot Tree Save Areas, or translated the ordinance into a defensible Tree Protection Plan. The earlier that work is done, the easier it is to avoid redesign, payment shock, and permit delay.