If you have a federal discount pass the rangers will stop by to verify the pass number and that you are the authorized pass holder. They also do a good job of verifying accurate payment. Last time there I over paid by a day and they stopped by to have me pay the right amount so I didn't over pay. Good people up there.
I've never been asked for I.D. If you cause trouble the forestry department will have the police come out to you. But only if you are causing trouble with other people, or being very unsafe.
Nope. They don't ask for. I.D. either. You just put a name on the envelope, stuff the money (or a check) inside and drop it in the box. Probably could even be fake, no ones ever asked me for proof.
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