Thanks for the OT move.  I thought there already was a Wild Edibles thread, but couldn't find it to bump.

Yes wintergreen berries & tea.  Stuffed a trout with the berries once, added a nice tart bump.

Blueberries, strawberries, rasperries, saskatoons, pincherries are all on the menu when available.  As a child my family used to spend whole days picking berries in the bush.  Followed by a day or two of cleaning & jamming.

I'm wary about mushrooms.  Mom picks them.  If I'm with someone who's confident then I'll eat them.  A couple years ago someone picked a bunch of morels and at the campfire said, "If only we had some butter."  I pack butter!  So we had fried speckled trout with morels.  Yummy!

Sumac tea is good too.

Pretty sure you can pick the fruit in parks.  Back when the family would pick we would get our spots from the park staff and often picking in the park.  That was 25 years ago, maybe things changed.  The distinction being that you can't uproot a plant, but you can pick the berries. 

Proper mushroom picking is cutting the base so it can re-sprout.  Yanking out of the ground is bad form.

Part of me wants to try the Survivorman diet during a trip.  I'd still pack food, but just try to snare something small or catch some frogs.  Legally, of course.