I had to chase off repeat trespassers just last Friday. A neighbor gives them permission to hunt his property, but tells them they can hunt mine. These are repeat offenders. I chased them off and then got steamed and got the tractor out so I could go to the far side of the property, where I found them hunting on my property, out of view of the house. Of course, it is always a crippled bird they are after, but it was funny to hear them debate my property line (clearly marked with posts). They tried getting me to give them exclusive permission... like they had on neighbors property. I told them no, and also let them know that they are not exclusive on the neighbors, that others hunt it. I think they pay good money to have exclusive and all 4 of them had big eyes when I told them... I still chuckle to myself when they say they were after a cripple but then say they were on neighbors property... such idiots. Expensive shotguns, expensive dogs, all the fancy gear, no brains...
I took my shotgun on the 4 wheeler years ago to run some trespassers off, decided after that, I wanted to be unarmed so I would not be tempted to point my gun at them, not even accidentally.