Neighbor Tree Disputes in Montana: Branches, Boundaries, Fallen Trees

Who owns a tree near the property line?

Montana's property code answers this by looking at the trunk. A tree whose trunk stands wholly on one owner's land belongs exclusively to that owner, and the code says so even when its roots grow into the land of another. Where the canopy hangs and where the roots run do not change who owns the tree.

That is simple on paper and harder in a yard, because it depends on knowing where the line is. A fence in the Bitterroot or around Missoula is not always on the surveyed boundary. If ownership of a tree matters, for a removal or for a disagreement, the line needs to be established by a survey, not by the fence or by memory.

What if the trunk sits right on the boundary?

The same part of the code says that trees whose trunks stand partly on the land of two or more adjoining owners belong to them in common. A true boundary tree is shared property. In practice that means neither neighbor should treat it as theirs alone to remove or cut hard, and decisions about it are best made together and written down.

When we assess a boundary tree, we ask both owners to be part of the conversation before any work is scheduled. An arborist can tell you what the tree needs. Who has the right to approve the work is a legal question for the owners and, if they disagree, for an attorney.

Can a neighbor's tree be a legal problem just by growing?

The Montana Supreme Court looked at this in 2012 in a case from the South Hills of Missoula, Martin v. Artis. An uphill owner sued the neighbors below because their tree had grown tall enough to block much of his view of the city, the valley and the mountains. He called it a nuisance.

The court upheld the dismissal of that claim. It concluded that a naturally growing tree obstructing a view did not meet the standards for a nuisance under Montana law. For most homeowners that is the practical point: losing a view or sunlight to a neighbor's healthy tree is a matter for a conversation or a private agreement, not something this opinion gives you a claim over.

What about roots and trunks that cross the line?

The same case had a second part. The uphill owner also alleged that the tree itself encroached over the common fence and that its roots had grown onto his property and were starting to buckle the boundary fence, and that the neighbors knew and refused to act. The court held that those allegations adequately stated a claim for trespass and sent that part of the case back to the district court.

Read that carefully. The court did not decide who would win, only that the claim could go forward. It also noted that other states have developed many different rules about trees between neighbors and expressly declined to adopt specific rules in that case. So Montana's law on encroaching trees is less settled than a quick internet search suggests. Our guide to tree roots near foundations, sewers and sidewalks explains what roots actually do and do not damage.

Can you cut branches that hang over your yard?

This is the question we hear most, and it is the one to be careful with. Many websites state a general rule that you may cut back to the property line. Neither Montana source we read for this guide sets that rule out, and the Supreme Court opinion declined to adopt specific rules for trees between neighbors. We are a tree service, not a law firm, so we will not tell you what you are entitled to cut.

What the Montana code does say is what happens when someone injures a tree that is not theirs. A person who cuts down, carries off, girdles or otherwise injures a tree on another person's land without lawful authority is liable to the owner for the damages. If the act was casual and inadvertent, or done believing the land was their own, the liability is the amount of the damages. If it was willful, wanton or malicious, the code makes it three times the damages.

That is a strong reason not to reach over the fence with a chainsaw. Heavy cuts on one side can destabilize or kill a tree, and so can topping, which we explain in our guide to why tree topping fails and what to do instead. Talk to the neighbor first, get agreement in writing if you can, and have the work done to pruning standards.

What if a neighbor's tree falls on your property?

Start with safety and your own insurer. The Insurance Information Institute says that if a tree hits your home or another insured structure, your standard homeowners policy covers the damage, and that insurers generally do not spend time working out where a tree came from. Where the tree stood on a neighbor's property, your insurer may try to collect from the neighbor's insurer, a process called subrogation.

The Institute also notes that negligence is what changes the picture, for example a diseased tree or one that was not properly maintained. Whether a particular owner was negligent is a legal question that depends on what they knew and when. Our guide to what to do when a tree falls on a house walks through the first steps and the insurance side in more detail.

How do you raise a concern about a neighbor's tree?

Before a failure, the useful thing is to make the concern specific. A general worry about a big tree is easy to dismiss. A dated note that says the tree has a cracked union over your garage, with photographs, is not. If the neighbor agrees, a tree health and risk assessment by an ISA Certified Arborist gives both households the same facts, and our guide to the signs a tree is about to fail shows what an assessment looks for.

Keep copies of what you send and when. If the tree is in a public boulevard instead of a yard, it is a city question, covered for Missoula in our boulevard tree and permit guide.

When do you need an attorney, and when an arborist?

An arborist answers questions about the tree: its condition, the likelihood of failure, what pruning it can tolerate, and what work would cost it its health. An attorney answers questions about rights: where the line is in law, what you may do without the neighbor's consent, and what to do if damage has already happened. Real disputes usually need both, in that order of facts first.

HJ can provide the tree side through our tree services, including a written assessment both neighbors can read. For related topics, browse the Montana Tree Guide.

Call HJ Property Care & Tree Service at (406) 215-7319 or request a tree assessment and an ISA Certified Arborist will look at the tree with you.

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