Diggem, this is exactly the point! There's a lot of areas where people lament that they are supposedly told are off-limits to detecting. And the citations they come up with, are fuzzy things about cultural heritage, or .... don't disturb the vegetation .... or indian fossils rules, etc.. blah blah. So some isolated ranger gives such an answer, or some isolated park does indeed boot persons, so all of the sudden, people circulate on the net that their state is off-limits. So what do they do? Rather than avoid *just* that one ranger, or *just* that one park, they start asking more & more questions, petitioning, etc... And before you know it, there WILL be a state-wide rule that DOES specifically mention metal detecting by name. It seems we are our own worst enemy, eh?
I mean, I bet if I walked into city hall in MY city, with a shovel in my hand, and asked "can I metal detect in the parks?" I bet I'd get a "no" too. But the truth is, I can go anytime I want here, and as long as I'm not a nuisance (using due discretion, go at low traffic times after 5pm, etc...) NO ONE REALLY CARED.
An example of this was the state of Utah, where ........ no specific rule existed (barring things that could be "morphed" if you tried hard enough). But guess what? Because of all this fear some md'rs have ("oh no, I better check at each kiosk, or write letters to the state park's dept, etc...), apparently the state of Utah issues a "clarification" to all their state parks, that specifically, now, disallows md'ing in state parks. But get this: the reason given for this "clarification", was "due to the many inquiries we receive each year, we will clarify the state's position ..." blah blah blah. You see how perhaps no one really gave a durn (barring some isolated incidents, or someone digging a truly sensitive site), but NOW you get a rule written, to address your pressing issue.