Although there might be state to state variations in National Forest law, I don't believe there is (DON'T hold me to that). In New Mexico we have lots of National Forest (public land) and that is one of the most popular places for hunting. You can only open-carry without a concealed weapons permit. Also there is occasionally wildlife protection periods where no "hunting" weapons are allowed, but I believe concealed weapons are probably ok. Call your National Forest headquarters for the correct info.