After our recent fires, some people blamed plants and trees as fuel. Some species are more flammable than others. UC ANR puts it plainly: all plants can burn under the right conditions, and where a plant is placed matters more than what type it is. Dead and dry material is what carries fire, and a garden full of it is a hazard.
The highest fire risk is where homes meet wildland. The rules below apply to homes in State Responsibility Areas and in locally mapped Very High Fire Hazard Severity Zones, not to every property.
The first five feet is its own zone
The state Board of Forestry has written rules for this zone, called Zone 0. They were adopted on August 19, 2026, and withdrawn for revision on September 8, 2026, so check whether they are in force where you are. Some cities already enforce their own. Once the state rules take effect, existing homes get several years to comply.
What matters for maintenance: no bark mulch or wood chips in this zone. Use rock or decomposed granite instead. No plants against the wall or under the eaves, within two feet of a window, door or vent, or within five feet of an attached deck. Past that, use only low, soft plants. Keep the lawn under three inches.
Take dead plants off the property. Chipped prunings used as mulch can stay, everywhere except Zone 0. Keep the roof and gutters clear, branches ten feet from the chimney, and no limbs over the roof (California Public Resources Code section 4291).
Zone 1: five to thirty feet
State law already sets two more zones for homes in these areas, and they are in force now.
In Zone 1, remove dead and dying plants, leaves and pine needles, roof and gutters included. Keep branches ten feet from the chimney. Clear anything that burns from under decks and stairs. Keep tree branches ten feet apart, more on a slope. Move firewood out to Zone 2 unless it is fully enclosed.
Zone 2: thirty to one hundred feet, or to the property line
Mow annual grass to four inches or less. Leaf litter can stay, up to three inches deep. Remove dead wood on the ground and in the trees. Limb up the trees you keep, at least six feet off the ground. Leave space between shrubs and trees. Clear ten feet down to bare soil around a woodpile.
During a fire
Do not hose the property down with municipal water during an active fire event; it draws on the water the fire department needs. Irrigate on the normal schedule.
The full rule, with its illustrations of Zone 0, is in Southern California Landscape Maintenance: Ecological Maintenance, Simplified, at rootandbranchdesign.com/book. The first chapters are free to read at rootandbranchdesign.com/book/sample.
Dead and dry material is what carries fire, and a garden full of it is a hazard.