I have a first hand story from when a group of us 4-wheel drive enthusiasts took a weekend trip to the Ouachita National Forest. We did this pretty often back in the day, still do occasionally but the moneys tighter, so it's not as frequent. This was on one of our earliest trips, and we had stopped for lunch on top of a mountain on an old logging trail. We had set up the grill, gotten situated, and two rough characters emerged from the woods with a riot gun and a AR, and asked just what exactly did we think we were doing. We carefully explained that we were just fixing lunch, and that they were welcome to join us if they'd like. They declined, took a seat on a log about twenty yards away - just far enough to be able to watch us all easily, but close enough to hear what we had to say. We quickly finished up, loaded back into the trucks and made dust. They melted back into the woods. When we stopped later, a couple of the other guys told us they had noticed a couple of other fellows in the woods just watching.
Here's the thing, there were 7 or 8 trucks and about 20 of us there, including wives and girlfriends and some kids. I was the only one armed. It gives me a bit of a cold chill to think what might have happened if there were only three or four of us in a couple of trucks. One CCW gun against an AR and a pump shotgun plus two more in the bush isn't exactly good odds. I can't really describe their demeanor in any word except menacing. Flat out. Once they had settled on the log, they tried to be nonchalant, but there is no doubt in any of our minds that they had, or were making plans. To this day, the only reason I'm sure something worse didn't happen is because there were so many of us. We aren't exactly an easily intimidated group, but that little confrontation scared us pretty bad. They certainly weren't going to allow us to stick around, much less wander off the logging trail. After that, we never went back to that particular trail and we stayed well armed.
Now, this is also a part of the country where during the 1980s the FAA issued warnings to private pilots not to fly below a certain altitude, as there were reports of people on the ground shooting at airplanes, supposedly confusing private pilots for the DEA spotter planes. It was a pretty lawless place apparently, especially if you are an outsider. In the 1990s the DEA cleaned out large chunks of the Marijuana fields in the national forests, supposedly arrested most of the really big growers, but it's tradition there and I can't imagine that made the forests any safer. I also read in a newspaper years ago that that portion of Oklahoma had the highest rate of missing persons reports out of the state.
We used to not put much faith in what we heard about the dangers in the National Forest, but that little experience certainly made us believers. It's something to think about. In terms of police presence, there is probably less in the big forests and parks than there is in rural areas, much less cities. And when you get off the paved areas, you are pretty much on your own. No cell service, no place to flag down travelers who may help you, ect. You best be prepared.