Sonoma County, CA Landscaping Rules: Weed Ordinances (2026)

Chapter 13A of the Sonoma County Code is the county's weed-abatement and hazardous-vegetation ordinance. Section 13A-4 imposes a duty on every owner of real property in the unincorporated area to abate hazardous vegetation and combustible material. The chapter implements California Public Resources Code §4291 and the 2019 California Fire Code as locally amended. Defensible space requirements: Zone 1 ('lean, clean, and green') extends 30 feet from any building or structure (or to the property line), where dead vegetation and combustible debris must be removed and irrigated plants kept healthy; Zone 2 ('reduced fuels') extends from 30 to 100 feet (or to the property line) and allows more natural vegetation but requires thinning, spacing of trees and brush, and removal of ladder fuels. Additional clearance — out to 100 feet or further depending on slope, fuel load, and fuel type — may be required at the Fire Warden's discretion. Roadside and driveway clearance: 10 feet horizontal and 13 feet 6 inches vertical for emergency-apparatus access. The Fire Warden/Fire Marshal is the enforcing officer and may use the county's code-enforcement administrative procedures. Inspections begin around June 1 each year when the State Fire Marshal declares fire season, with letters and door-tag notices sent earlier in the spring. The CAL FIRE State Responsibility Area (SRA) covers much of rural Sonoma County and overlays additional state defensible-space rules under PRC §4291.