(Background information) My neighbor and I do not talk much. We had a definite, ongoing issue with him letting his dog use the bathroom in my yard, without him cleaning it up. If he had cleaned it up there'd be no issue. I LOVE DOGS! Anyways, neighbor's yard is totally neglected and I want to have his trees trimmed away from my roof. Here's my question: Would it be rude or improper to trim only the side of the tree that is touching my roof? These are not my trees, and I am SURE he would have an issue with the tree guy going onto his property. I guess what I worry about it whether it may make the tree have an uneven weight and possibly fall on his house. If that happened, would I be liable? I don't see him ever handling the trees on his own. This is a man who hasn't cut his backyard at all this year. He cut it once last summer. Let me know what you think.