Seattle, WA Tree Protection: Protected Tree Species (2026)

Because Seattle's goal is to protect and grow tree canopy cover (one important measure of the health of the urban forest and people who depend on it), Seattle's Tree Protection Code, Seattle Municipal Code (SMC) 25.11, limits the number, size, and type of trees that may be removed from private property. [...] Tree Protection on Private Property — Our tree protection requirements vary based on the size (tree tier), species, whether there is construction occurring or proposed on the lot, and the zoning of the property. Certain trees are protected and may not be removed unless specific requirements are met. If you unlawfully remove a tree, the penalties can be expensive. [...] All tree service providers doing the following type of commercial work defined in SMC 25.11.130 in Seattle in exchange for financial compensation must be registered with the Seattle Department of Construction and Inspections (SDCI): Reportable work includes: The removal of live branches 4 inches in diameter or greater; Pruning, or the removal of live roots 2 inches in diameter or greater; Removal of live branches constituting 25 percent or more of a tree's foliage-bearing area; [...] Removal of any Tier 1, Tier 2, Tier 3, or Tier 4 tree; Consulting Services: The assessment of the health or hazard risk of any Tier 1, Tier 2, Tier 3, or Tier 4 tree (trees 6 inches DSH or greater).