Contributed by Seattle Tree Care
July 27, 2023
Seattle’s Tree Protection Code is complicated and lengthy. There are many factors to consider when determining what protections are in place for each specific tree. Different parameters apply to different species on different types of properties.
The team of Certified Arborists at Seattle Tree Care studies the code and its implications to fully understand its many nuances. The most recent ordinance, which goes into effect July 31, imposes stricter tree removal restrictions on private property not undergoing development.
Below is a brief and simplified overview of the new regulations for trees on private property not undergoing development. Tree protection regulations are different for properties undergoing development, properties located in an Environmentally Critical Area (ECA), and public property.
There are many other elements of code application that are not covered here. For questions about a specific tree, contact the team of ISA Certified Arborists at Seattle Tree Care.
Starting July 30, 2023:
A tiered classification system will replace the previous Exceptional and Significant designations. A tree’s protected status is determined by its tier. Tree species and size, measured at Diameter at Standard height (DSH), are two important factors that separate the tiers.
Tier 1 trees are part of the Heritage Tree Program, a joint effort by Plant Amnesty and the City of Seattle.
- Tier 1 trees need a permit to be removed and must be replaced or a fee paid in-lieu.
Tier 2 trees include most species with a DSH of 24 inches or greater.
- Tier 2 trees need a permit to be removed and must be replaced or a fee paid in-lieu.
Tier 3 trees include most species with a DSH between 12 and 24 inches. Tier 4 trees have a DSH between 6 and 12 inches.
- Up to three Tier 3 and 4 trees can be removed in a one-year period without a permit in Downtown and Industrial property zones.
- In all other zones, Tier 3 trees need a permit to be removed and must be replaced or a fee paid in-lieu.
- Up to two Tier 4 trees can be removed in a three-year period without a permit in the following zones: Neighborhood Residential, Lowrise, Midrise, Commercial, and Seattle Mixed Zones.
In order to be approved for removal, a tree must be hazardous, dead, causing severe conflict with infrastructure, or have serious insect or disease issues.
Trees with a DSH smaller than 6 inches are not regulated by the SDCI.
If you have questions about the Tree Code, the Arborists at Seattle Tree Care are here to help. You can contact the Seattle Tree Care team via their website, seattletreecare.org, or by email: firstname.lastname@example.org.