In cases like this where there seems to be a multitude of policies from different jurisdictions, it may sometimes be difficult to see which one takes precedence. I would think that the Forest Service policy regarding nudity must be in writing somewhere. Wizard, maybe you can ask Brad if he can provide the written policy (if there is one). Generally in law, the applicable policy that comes from the highest level authority supersedes the lower level policy. This is usually called Federal preemption. Since the USFS is Federal, there policies should be the applicable ones -and they can legally overrule the State, County and City policies.