Auburn, WA Landscaping Rules: Tree Removal & Heritage Trees (2026)
Tree removal permit rules in Auburn, WA, sometimes called heritage tree, protected tree, or street tree ordinances, list which trees require a permit before you can cut them down.
Key Facts
- Protected size
- 6-inch evergreen or 4-inch deciduous, measured 4 ft up
- Excluded species
- Alders and cottonwoods do not count
- Removal permit path
- Alternative landscape plan under ACC 18.50.080
- Crown-loss threshold
- Pruning over 50% of live crown counts as removal
- Replacement ratio
- 150%-200% of original size, same species
Summary
Auburn requires developers to retain every "significant tree" (six-inch evergreens or four-inch deciduous trees) standing in a project's required perimeter landscaping area under ACC 18.50.045, and pruning that strips more than half a tree's live crown counts as removal, triggering the same enforcement track as an unauthorized removal.
A. Retention. In the required perimeter landscaping area, applicants shall retain all significant trees. A significant tree means a healthy evergreen tree, six inches or more in diameter measured four feet above grade, or a healthy deciduous tree four inches or more in diameter measured four feet above grade. Alders and cottonwoods are excluded from this definition. ... Significant trees may also be exempted from this requirement if it is determined by the planning director based on satisfactory evidence pursuant to report prepared by a consulting arborist certified by the International Society of Arboriculture. The report submitted to the city shall demonstrate the significant tree is: 1. Damaged; or 2. Diseased; or 3. Has weak structural integrity that poses a safety hazard. If additional significant trees are to be removed, the applicant shall seek approval of an “alternative landscape plan” from the planning director under ACC 18.50.080.
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through Ordinance 7023, passed July 6, 2026).
Full Breakdown
045, adopted by Ordinance 6387 in 2011, defines a protected "significant tree" as any healthy evergreen six inches or more in diameter (measured four feet above grade) or any healthy deciduous tree four inches or more in diameter, excluding alders and cottonwoods, and requires applicants to retain every significant tree standing in a project's required perimeter landscaping area. If regrading would endanger a retained tree, the applicant must build a dry rock wall or well sized to protect the root zone. The retention duty can be waived for trees in driveways, curb cuts, sight-distance areas, utility corridors and storm drainage facilities, or for any tree an ISA-certified consulting arborist certifies in a written report as damaged, diseased, or structurally hazardous.
080. 045(C). 070(C)(1) treats pruning that removes at least half of a tree's live crown as tree removal, triggering the same enforcement track as an unauthorized removal. 070(D).
Violations & Fines
A property owner who removes a significant tree without an approved alternative landscape plan, or who prunes it past half its live crown without authorization, faces a Chapter 1.25 ACC code compliance case. The corrective action plan must replace an unlawfully removed tree with stock at 150 percent of its original planted size, or 200 percent for a tree that was excessively pruned, in the same or a similar species approved by the planning director.
Frequently Asked Questions
What counts as a "significant tree" in Auburn?
Can I remove a significant tree if it's diseased?
Does trimming a tree count as removing it?
Sources & Official References
Other rules in Auburn
Compare Auburn to another location·View the Washington landscaping rules overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.
Tree Removal & Heritage Trees in Nearby Cities
How other cities in King County handle tree removal & heritage trees.