These are my personal rules. There are as many or as few rules as you care to impose.
1) Don't get mugged.
2) Read any posted signs for mention of " Metal detectors" Don't be a pest. Dig neat. Don't dig when its too dry to cut a plug. Show any employees (if present) the junk and sharp things you removed. If they ask you to leave, leave quickly quietly and don't let them see you back there lol. These rules apply to all state parks. Avoid National Parks and monuments.
3) Don't be a martyr to beaurocracy. Only ask permission if there's someone standing there blockading your detecting route. If theres someone standing there you are in too public of a place and you're too high visibility. When I am in the field I encounter park rangers who are super nice and wish me luck. They are out with their buckets and tongs picking up trash. I am also picking up trash. I don't ask them if its ok to detect since they would say " No." Instead I show them how a good unobtrusive detectorist can be. I don't go near the air conditioned toll plazas or ranger stations. If you ask there they will be forced to tell you you can't detect, then they'll have to put up signs for the rest of us that they didn't even know existed lol. I have a different view on this so don't take my word as gospel.
