Most state or county owned land trap only. There are very few that allow hunting. It actually takes quite a bit of state/county staff to moniter or regulate the hunting. Or else just anyone could be running around out there fully armed. Also, a few maverick hunters sometimes stray into areas where they shouldn't be. I can't recall the exact % but it's something like 13 out of 17 hogs need to be killed to counter act the rate of reproduction. So it's a frustrating practice.
As far as the trappers go, most of them have it figured out that they have a stipulation in the contract that they are the only ones allowed to trap that land. There are not too many trappers that are licensed and they kind of all agree to stick together on that one.