Edibility Caution:

This mushroom VERY CLOSELY resembles the Deadly Galerina (Galerina autumnalis) and SHOULD NOT BE EATEN without experience with both species, and microscopic confirmation of your ID. Pholiota mutabilis has smooth spores, while the Deadly Galerina has rough spores. Otherwise, they are quite similar in season, habitat, size, shape, spore color, annulus, etc.

Description for these photos:

Cap 1.5-7cm diameter. Hygrophanous, lighter in the center. Gills tan, turning rust-colored, decurrent, but breaking easily from stipe. Stipe 2.5-9cm long, .5-1cm thick, curving, cream to tan, fibrous, peeling into darker scales. Small, fibrous, rust-colored annulus lost with age. Odor initially resembles burning plastic, but becoming mild and fruity. Spore print dark rusty-brown. Growing in large, cespitose clusters on huge, very soft (brown rot) hardwood log (probably oak).