Tacoma, WA Tree Protection: Protected Tree Species (2026)
Key Facts
- Conifer threshold
- greater than 30 inches DBH
- Madrone threshold
- greater than 12 inches DBH
- Onsite mitigation ratio
- 2:1 replacement planting
- Offsite mitigation ratio
- 4:1 replacement planting
- Applies within
- designated Biodiversity Areas only
Summary
Inside Tacoma's designated Biodiversity Areas, a conifer over 30 inches DBH or a madrone over 12 inches DBH counts as an 'exceptional tree' that development must retain; removing one requires replacement planting at double the normal mitigation ratio.
“Exceptional tree” means a tree or group of trees that because of its unique historical, ecological, or aesthetic value constitutes an important community resource, and is determined as such by the Director according to standards and procedures promulgated by the Department of Planning and Development. Conifers greater than 30 inches DBH, and Madrone greater than 12 inches DBH are considered exceptional trees.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4946110; v22 updated 2026-07-28).
Full Breakdown
TMC Chapter 13.11, Critical Areas Preservation, implements the state Growth Management Act's mandate that Tacoma designate and protect critical areas, including Fish and Wildlife Habitat Conservation Areas. Within a designated Biodiversity Area, TMC § 13.11.550 requires development to retain 'exceptional trees', defined as conifers greater than 30 inches DBH, madrones greater than 12 inches DBH, or any tree the Director finds historically, ecologically, or aesthetically significant, along with significant tree groves of eight or more 12-inch-plus trees forming a continuous canopy. TMC § 13.11.560 sets the mitigation ratio for lost exceptional trees at 2:1 if replanted onsite or 4:1 offsite, twice the standard 1.5:1/3:1 ratio for ordinary vegetation.
Violations & Fines
A project that removes exceptional trees without meeting these retention and mitigation standards can be denied Minor Development review and pushed into full Development Permit review under TMC § 13.11.550E.
Frequently Asked Questions
What counts as an "exceptional tree" under Tacoma's critical areas code?
What happens if an exceptional tree is removed during development?
Sources & Official References
Other rules in Tacoma
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Protected Tree Species in Nearby Cities
How other cities in this county handle protected tree species.