These large fleshy gilled mushrooms were growing straight out of the moss covered leaning trunk of a living tree. I include one phot of the leaves of the tree in case its identity is a clue to what Fungi it might be host to. iNaturalist says it looks like a Boxelder (Acer negundo), which seems not unlikely around here.

This is in the damp deep valley of the Enlow Fork of Wheeling Creek on the Allegheny Plateau of southwestern Pennsylvania, which is densely covered in mixed deciduous woods, just above the floodplain at an altitude around 272 meters (892 feet).