Civil Code 833 and 834: who owns the tree

The text

§ 833. Trees whose trunks stand wholly upon the land of one owner belong exclusively to him, although their roots grow into the land of another.

§ 834. Trees whose trunks stand partly on the land of two or more coterminous owners, belong to them in common.

Both sections date from the original 1872 Civil Code and have not been amended. Their age is part of why they are so often misread: the language is plain, and people argue from the canopy anyway.

What 833 means in practice

• The tree owner is responsible for the tree: its condition, its hazard, and the damage its roots and limbs cause when that damage rises to a nuisance.
• The neighbor owns nothing of it, including the fruit on the branches over their yard, and may not cut past the property line.
• The neighbor may trim encroaching branches and roots to the line at their own expense, reasonably and without injuring the tree. That right comes from common law and its limit from Booska v. Patel, not from 833 itself.

What 834 means in practice

• Both owners own the whole tree, not each their own half. Neither may remove it, top it, or seriously injure it without the other's consent.
• A co-owner who does is liable to the other, and Civil Code 3346's double and treble damages apply.
• Responsibility for the tree is shared. The Code sets no formula; owners usually agree a split, often by canopy share, and an arborist's maintenance specification is what they agree to.
• A city removal permit for a boundary tree generally needs both owners' consent, and some cities will not accept an application from one owner alone.

How the trunk is measured

At the ground, where the trunk meets the soil, against the actual line. Not at chest height, where a lean can put the trunk visually on the wrong side, and not against the fence, which is evidence of where someone once thought the line was and nothing more. Where the trunk is within a foot or so of the apparent line, or the fence and any monuments disagree, a licensed land surveyor has to settle it before anyone acts. The arborist's report states the trunk's position relative to the fence and any monuments found, says plainly whether a survey is needed, and does not guess at the line.

Where it goes wrong

1. A neighbor assumes the overhang is theirs and removes limbs on the owner's side: trespass, 3346 damages.
2. A co-owner removes a boundary tree because "most of it was on my side": liability to the other co-owner, plus the city's unpermitted-removal penalty.
3. Both parties argue from the fence line for a year before anyone measures the trunk or pulls a survey.

See tree on the property line for what the report does and what to do first.

Sources

1. Civil Code § 833; § 834, California Legislative Information.