My neighbor's trees are a fire hazard to my house. What can I do?

What is actually happening

Defensible space zones are measured from your structure, not from your fence. Zone 0 (0 to 5 feet), Zone 1 (5 to 30 feet) and Zone 2 (30 to 100 feet) routinely run across the property line, and the worst fuel in them is often a neighbor's: a eucalyptus windrow, a juniper hedge, a dead Monterey pine, a bay laurel thicket under a redwood canopy. Your inspection notice, or your insurer's letter, names vegetation you do not own.

The useful distinction is between fuel and hazard. A green, healthy tree that happens to be a flammable species is fuel; the law leaves that to each owner and the fire district. A dead or dying tree, or one dropping limbs over your roof, is a hazard in the ordinary sense, and that is where the neighbor's duty of care and your notice come in.

What California law says

• Each parcel, each owner. Public Resources Code 4291 requires 100 feet of defensible space (or to the property line) around structures in State Responsibility Areas; local fire codes extend it in Local Responsibility Areas. The obligation runs with the parcel the vegetation is on.
• No private right to clear the neighbor's land. The self-help rule still applies to overhang, within Booska v. Patel; nothing in 4291 lets you cross the line.
• Hazard is the claim. A dead or structurally unsound tree the owner knows or should know about is the owner's liability when it fails (Civil Code 1714); written notice with an arborist's findings establishes "should know." See dead or leaning tree next door.
• Enforcement is public. Fire districts and CAL FIRE inspect and can order abatement on the vegetation owner's parcel; the complaint route is through them.

What your city adds

Two things pull in opposite directions. Fire codes in Marin, the East Bay hills, the Peninsula hills and the Santa Cruz mountains push for removal of hazardous fuel; protected-tree ordinances in the same cities restrict removal, with a few fire-hazard exemptions or expedited paths. Which trees can come out under a fire exemption and which still need a permit is a city-by-city question covered on California Fire Defense's permits guide. Eucalyptus and Monterey pine are exempt from protection in several cities, which makes them the easiest fuel to get removed by agreement.

Fire hazard and defensible space guides

The vegetation-management side of this problem, on your parcel, is California Fire Defense's work. Start here:

• Defensible space: zones, state law, inspections
• Zone 0: the ember-resistant zone rule
• Trees and fire: species, spacing, ladder fuels
• Insurance non-renewal and documentation
• Fire-mitigation tree permits by city

What the report does for you

1. Documents the neighbor's trees from your side: species, condition, dead wood, fuel continuity to your structure, and distance into your zones.
2. Separates fuel from hazard: which trees are a structural risk to your house, and which are merely flammable.
3. Gives you the written findings to attach to a notice to the owner, a complaint to the fire district, and a response to your insurer.
4. Specifies the overhang you may trim on your side.
5. Routes your own parcel to a Defensible Space Plan when that is what the inspection or the insurer actually needs.

Dispute Assessment Report, from $850. Same arborist, one visit, both reports when both are needed. Start the report

What to do this week

1. Read the notice or the insurer's letter for what it actually names; much of it is usually on your side and fixable.
2. Photograph the neighbor's trees from your zones, dated, with the structure in frame.
3. Talk to the neighbor with the inspection standard in hand; many have the same letter.
4. Start a report or text (415) 881-0124 with the photos and the letter.

Sources

1. Public Resources Code § 4291.
2. Civil Code § 1714; Booska v. Patel (1994) 24 Cal.App.4th 1786.