Sonoma County, CA Fire Regulations: Brush Clearance (2026)
Key Facts
- Ordinance
- Sonoma County Code Chapter 13A
- Core defensible space
- 30 ft around structures
- Extended zone
- Up to 100 ft by slope/fuel
- Roadside clearance
- 10 ft minimum
- Tree limbing
- Branches up 6 ft from ground
- Non-compliance
- County abatement + lien
Summary
Sonoma County Code Chapter 13A requires owners of parcels in the unincorporated area to maintain defensible space and abate hazardous vegetation year-round. Improved parcels in the Local Responsibility Area must keep 30 feet of defensible space (up to 100 feet if conditions require), limb trees, and clear roadside vegetation. Non-compliance can be abated by the County with costs liened to the property.
(1) (A) Maintain defensible space of 100 feet from each side and from the front and rear of the structure, but not beyond the property line, except as provided in subparagraph (B). The amount of fuel modification necessary shall consider the flammability of the structure as affected by building material, building standards, location, and type of vegetation. Fuels shall be maintained and spaced in a condition so that a wildfire would be unlikely to ignite the structure. This subparagraph does not apply to single specimens of trees or other vegetation that are well-pruned and
Full Breakdown
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.
Violations & Fines
Failure to maintain 30-foot (up to 100-foot) defensible space, limb trees, or clear roadside vegetation on a covered parcel is a public nuisance under Chapter 13A. Owners receive a notice of violation and 30 days to abate; non-compliance allows County abatement with costs, fees, and penalties placed as a property lien. Civil and criminal penalties under Sonoma County Code 1-7/1-7.1 and PRC 4291.1 may apply.
Frequently Asked Questions
How much defensible space does Sonoma County require?
What happens if I don't clear my brush?
Sources & Official References
Other rules in Sonoma County
California rules heatmap·Compare Sonoma County to another location·View the California fire regulations overview
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