Pretty much but it can get a bit sketchy on some of the small stuff. normally A good rule of thumb is if the county mows it the county owns it. It's sort of like the 440 rule lots and lots of hunters think it's a law that applies to all situations but in reality it's doesn't. For instance 440 only applies on private ground you don't have permission for any other land you're on you could be right next to a guy's house without permission....baring signs specifically forbidding it. Mind you that 440 one comes in mighty handy when hunting the river.
As for the interstate analogy one time back in the mid-90s probably about 1 in the afternoon on opening day of deer season my dad and I came across a group of guys that were doing a deer Drive in the median of the interstate. You ever take that chunk that cuts through painted Canyon there's a point there where the interstate splits and there's trees between the lanes and they were doing a deer Drive in there and they actually were in the process of gutting a deer when we went past. They did also give us one of the most hilarious visual of an nice Buck running across the Interstate in front of us and then watching him try to jump over the fence and needless to say his calculations were off by about four feet of vertical height cuz he smashed into that fence like a ton of s*** hit the ground and looked kind of a bit dazed and then just ran down the edge. This is the stretch of trees and brush I was talking about.