Let’s say about 100 years ago, a family planted an oak tree on the edge of their property. Over generations it’s grown into a magnificent tree that provides summer shade, autumn color and a swing for the neighborhood kids. You probably even liked the tree when you bought the house next door to it.

But today, its root system is invading your basement, its acorns bombard your yard and its huge limbs loom threateningly over your roof. By law, can you cut it down? Trim it? Turn it into a boat?

First, Determine Who Owns the Tree
You may assume the oak in question is part of the property where it was originally planted. However, in Illinois, tree ownership is based on the location of the trunk at the ground—and not the roots or branches.

A boundary tree straddles the property line
and is jointly owned by both property owners

Since this tree was planted on the edge of the property, look at the base of its trunk. If the trunk of the tree straddles the property line (even by just a few inches), it’s a boundary tree, which means the tree is jointly owned by your neighbor and you.

For a boundary tree, you share the responsibility of its care and or destruction. In fact, neither neighbor has the right to cut, damage, or significantly modify a boundary tree without the permission of the other.

An encroaching tree has its trunk on one side of the
property line and grows into a neighboring property

It’s an encroaching tree if the trunk base stayed on the neighbor’s property. The tree—and its responsibility—is considered theirs. If so, talk to your neighbor. Let them know they are required to ensure their trees’ roots or branches don’t cause damage to your property—and that they are liable for the damage.

And if They Still Do Nothing?
You have the right to protect your property from damage. You can trim a neighbor’s tree branches or roots without asking as long as you don’t enter their property.
Yet take care not to kill or harm the encroaching tree. If so, you would be liable for up to three times the tree’s value, which the Department of Natural Resources determines, under the Wrongful Tree Cutting Act.

In short, talk to your neighbor before doing anything to a boundary tree. And it’s generally safe to trim your neighbor’s trespassing branches and roots without asking—as long as you don’t enter the neighbor’s property or harm the tree.

Did that leaf you with questions? Send me This email address is being protected from spambots. You need JavaScript enabled to view it.. While I don’t handle tree encroachment lawsuits, it’s a problem that often comes up in my real estate transactions.

Written by Susan Jenks for Michael H. Wasserman, P.C.

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