I finally found one in the wild for the first time in several years. Only one, under a maple I think, in mixed maple/oak/tulip/beech mainly. I think it was too high for elms, so none of those around. Some black/yellow birch also, with nice wintergreen smelling inner bark. The tree here had young leaves with 3 large points and two smaller ones if I remember right, so I'm pretty sure it was a maple.