Sounds like you have an unfortunate situtation here. There are a couple things you could do. The first is to ask a male friend or family member to go ask him in a more direct way if you think that is the motivation he needs. A second option is to call the police and find out if there are any criminal laws that prevent him from doing that. A number of possible charges (depending on where you live) include criminal mischeif or destruction, trespassing (if he actually enters your property), illegal dumping and others. There may also be city or county ordinances where you live that specifically prevent your neighbor from doing this. Taking this one step further, if your neighbors actions and disregard for your wishes amount to a threat of violence in any way, that could be dealt with as well. I know it sounds silly to call the police over snow on your property, but a lot of what they do is deal with general disturbances like this (I did a lot of that kind of thing when I was a cop). Worst case scenario is there is no law to prevent your neighbor from doing this, but a stern talking to and promise to return by an officer might be all it takes to get him in line. Good luck in your situation and let me know if I can help further!