Multnomah County, OR Tree Protection: Tree Replacement Requirements (2026)

Portland's mitigation requirements under City Code 11.50 (Tree Permits) set replacement ratios based on the size of the removed tree at the time of removal: trees 12-19 inches DBH require 1 replacement tree, 20-35 inches require 2 replacements, 36+ inches require 3 replacements. For development projects removing multiple trees, an inch-for-inch replacement calculation may apply under Title 33 tree density standards. Replacement trees must be minimum 1.5 inch caliper (2 inch for street trees) and planted within 12 months of removal, with a 2-year establishment period. Preferred species are native Oregon trees (Douglas fir, big-leaf maple, Western red cedar, Oregon white oak, Oregon ash) and approved urban-adapted species from the Portland Parks Tree Selection Guide. On-site planting is required when space allows; fee-in-lieu to the Tree Planting Fund is permitted only if site constraints prevent on-site mitigation, at rates set annually (approximately $450 per inch of removed DBH in 2024). Heritage Tree mitigation is 3:1 minimum. Unincorporated Multnomah County MCC 39 requires replacement in SEC and SNR overlays. Developers violating replacement plans face permit revocation.