Iam sure this has been metioned but I would keep leave the stand where it is and leave a not saying that this person did not have permission to hunt on the land or build a stand on the land,also say that this is his one chance to either remove the stand and stay off the land or leave the stand and stay off the land and if does not comply you will get the fish cops envolved. and if you have to set upclose enough to see who it is when he returns.