Trees on a neighbor's property may encroach onto your property. State law varies, but generally, you may trim branches that overhang onto your property, as long as doing so doesn't damage the tree. You must get your neighbor's permission to enter their property to cut branches. If your neighbor's tree fell on your fence, yard, house, garage or car as a result of a storm, the neighbor has no obligation to remove the portion of the tree on your side of the property line and is not responsible for the damage the tree caused, unless they have reason to know the tree is dead, damaged, or has notice that it constitutes a threat. Some jurisdictions have recognized that the natural growth of trees includes shade, invading roots, leaves, and overhanging boughs, and that liability is reasonable when there is "sensible damage," such as a damaged roof, not mere debris from a healthy tree.