I say fry them all!!!! I have caught over 200 people in the last 4 years and I am sick of it. I work way to hard and spend way to much money for other people that don't have permission and act like they don't know what they did wrong (and everyone of them do)to mess up my hunting ground.
A good ass chewing and the game warden didn't do the trick I had a group of guys hunting my sanctuary 2 years ago ( i haven't even hunted that spot in 6 years)I stopped them and called the game warden we both chewed their ass big time. And low and behold this year the same 5 guys were in the same spot, and so I pressed charges.
In my dealings with tresspassers a ass chewing is just like a slap on the wrist for breaking a law, you don't get a slap on the wrist if you get caught with to many birds or pulled over for dui.
As far as posting the land I post the hell out of it but that doesnt seem to matter either unless there is a sign on every fence post they just say I didn't see the sign, but in SD it doesn't have to be posted, so my suggestion is learn the laws for where you are gonna be hunting and know where you can and can't be. Wether you are a local or a nonresident. LEARN IT,LOVE IT,LIVE IT, everyone else has to.