West Haven-Sylvan CDP (part), Washington County, Oregon Tree Protection: Tree Removal Permits Rules (2026)

Washington County's Community Development Code addresses tree protection primarily in Significant Natural Resources (CDC §422) and sensitive areas governed by Clean Water Services' Design & Construction Standards (riparian corridors along Tualatin River, Fanno Creek, Bronson Creek, Rock Creek). Unincorporated urban residential areas do not have a universal tree-removal permit requirement for private yards, but trees in CWS Vegetated Corridors (typically 15-200 ft from water features) cannot be cut without CWS concurrence. Cities impose stricter tree codes: Beaverton Development Code 60.60 and BC 9.04 require permits for removing trees over 10-inch DBH in protected areas; Hillsboro CDC 12.32 mandates permits for significant trees (≥6-12 inch DBH depending on type) in planned developments; Tigard's Urban Forestry Manual and TDC 18.420 require tree preservation plans for development and permits for removals from sensitive lands. Street trees in the county right-of-way are managed by the county or city public works department and cannot be removed without permit. Dead, dying, or hazardous trees receive expedited removal. Mitigation planting (1:1 to 3:1) required for permitted removals. ORS 527.620-527.770 Oregon Forest Practices Act governs commercial timber harvest in forestland, including portions of western Washington County around Gales Creek.