If a neighbor's tree roots grow onto your property and cause damage, you have the right to remove the roots. Your specific rights and remedies may vary depending upon local law. Check local statutes and ordinances, as well as with your homeowner's insurance carrier, before taking action. The general rule is that any part of the tree encroaching onto your property is yours to do with as you please. In fact, you could even be considered responsible for its maintenance. As such, you cannot charge a neighbor for the removal of the tree roots that are causing property damage. The tree roots are part of your property.

Removing the tree roots up to the boundary line is a reasonable course of action. Crossing property lines or removing part of the tree not on your property could result in a lawsuit. Any uncertainty regarding the location of the actual property line should be dealt with prior to digging.

Document the property damage and the circumstances surrounding it well before you begin to dig. There is a chance that your actions may cause the tree to die.  If it does, a neighbor could bring a lawsuit against you for the death of the tree. Your legal defense could rest on proof that the tree roots were invading your property and that you cut only on your property. Documentation may also be necessary should you need to make an insurance claim for property damage.  Make sure to obtain estimates of the cost on the property damage, take photographs, and keep careful records of the situation before, during, and after digging up the tree roots.