Sonoma County, CA Fire Regulations: Brush Clearance (2026)

Chapter 13A of the Sonoma County Code, 'Duty to Maintain Defensible Space and Abate Hazardous Vegetation and Combustible Material,' is the County's core brush-clearance ordinance for the unincorporated area. It declares that 'all hazardous vegetation or combustible material located on real property within the unincorporated area of the County of Sonoma is deemed a public nuisance.' It is enacted under Health and Safety Code sections 14930 and 14931 and complements Public Resources Code section 4291 for State Responsibility Area parcels (Title 14 CCR sections 1299.01-1299.05).

For improved parcels in the Local Responsibility Area, Section 13A-4 requires owners to maintain a 30-foot defensible space around all structures: grass cut to six inches or less (not to bare soil), tree branches limbed up six feet from the ground, shrubs maintained, and climbing vines cleared of dead material. Additional defensible space outward to 100 feet may be required depending on slope, fuel load, and fuel type. Owners must also keep a 10-foot minimum clearance along the roadside, remove tree portions within 10 feet of chimney outlets, keep roofs and gutters clear of debris, install a spark arrester, and post reflective address numbers. Compliance is required throughout the year. Agricultural crops/operations and cannabis cultivation buildings are exempt, but defensible space is still required around habitable dwellings and residential accessory structures.

Enforcement runs through the County Fire Warden/Fire Marshal. After a notice of violation and order to abate, owners have 30 calendar days to comply; otherwise the County may abate and place unpaid abatement costs as a lien on the property.