Property owners in every state have the right to trim the branches or roots of a neighbor’s tree that encroach onto their property, up to the property line, at their own expense. This right is called “self-help.” Self-help is an alternative to going to court.
The rationale is that self-help prevents the wasteful use of the court system to resolve comparatively minor disputes. It’s a trade-off: you have the right to cut and remove the encroaching branches or roots of your neighbor’s tree, right away, at your own expense (i.e., use self-help), instead of having to hire a lawyer, start a lawsuit, and wait for the courts to sort it out.
Using self-help saves you time and money, and keeps the courts from settling disputes between neighbors. In Minnesota, you have the option of using self-help or going to court, when using self-help is not practical or reasonable. In most other states, self-help is the exclusive remedy.