Butte County, CA Environmental Rules: Defensible Space (2026)

The three zones are defined at Section 38A-4(f): Zone 0 is the 'Ember-Resistant Zone' from 0 to 5 feet from any building or deck; Zone 1 is the 'Lean, Clean, and Green Zone' from 5 to 30 feet; and Zone 2 is the 'Reduced Fuel Zone' from 30 to 100 feet. Section 38A-6(a) sets the maintenance standard for each: Zone 0 must stay free of combustible materials and hazardous vegetation, limited to low-growing, high-moisture plants free of dead debris, and every chimney or stovepipe outlet must carry a spark screen with openings no larger than one-half inch. Zone 1 requires removing any tree or shrub limb within ten feet of a chimney outlet and clearing all dead or dying growth. Zone 2 allows weeds and dry grass only if mowed to four inches or less, with loose surface litter capped at three inches deep. Trees throughout Zones 1 and 2 must be pruned up to six feet from the ground, or one-third of the tree's height for shorter trees, and shrubs must be spaced to break up continuous fuel.

Subsection (b) extends the obligation across property lines: if a parcel within Zone 1 or Zone 2 sits within 100 feet of a building on an adjoining parcel, the owner must still meet the requirements needed to give that building its full 100 feet of defensible space. The Fire Chief can approve reduced firebreak requirements on steep slopes, near unique wildlife habitat, endangered species, or vernal pools, coordinating with soil conservation and wildlife agencies as needed under Section 38A-6(d). Retained shrubs and trees are allowed within firebreaks only if kept free of dead wood and spaced so crowns do not touch.