Sonoma County, CA Landscaping Rules: Tree Trimming (2026)

For ordinary trimming of a healthy tree on your own property, Sonoma County does not require a permit. The County's published defensible-space requirements (Permit Sonoma Fire Prevention, under Chapter 13A) do impose specific limb-clearance measurements near structures and roads: in the Local Responsibility Area, owners must 'prune trees to 6 feet from the ground' in both the 0-30 foot and 30-100 foot zones around buildings, remove branches up to 6 feet above the ground along roadways, and 'remove all portions of trees within ten feet (10 feet) of chimney' or stovepipe outlets. In the State Responsibility Area, similar clearance around chimneys and structures applies. Separately, owners should be careful: cutting that effectively removes or destroys a protected native tree (oaks and other listed species 6 inches DBH or larger) is regulated under the County's Tree Protection rules (Code Section 26-88-010) and may require a permit even if you call it 'trimming.' Trees designated under the Heritage and Landmark Tree Ordinance (County Code Chapter 26D) receive added protection. There is no county ordinance compelling you to trim a neighbor-overhanging branch; that remains a civil matter, though California's general right to trim overhanging limbs back to the property line still applies.