Kuehneromyces mutabilis, also known as Sheathed Woodtuft, is a medium-sized agaric that has an umbonate honey-brown to yellow hat, which dries from the centre, producing a two-tone effect. It also has yellowish or reddish-brown gills and a ring on the stem. It grows clustered on stumps and logs of broad-leaf trees, favouring birch.

Cap convex, becoming flattened with a blunt umbo, and hygrophanous; as damp shiny and greasy with a deep orange-brown colour towards the rim; often there is a disc of lighter flesh in the middle. It is cinnamon-coloured as dry. Gills initially light and later cinnamon brown and broadly attached to the stem and crowded. Sometimes somewhat decurrent. Spores are ochre-brown. Stem pale and smooth light cinnamon above the ring and below darker brown shaggily scaly.

Similar species include the lethally poisonous Galerina unicolor and Galerina marginata which have fibers and no stem scales.

Warning: This mushroom should not be gathered to be eaten because it is so easily confused with the deadly poisonous Funeral Bell, Galerina marginata. Only very experienced fungi foragers should consider gathering this species.

Kuehneromyces mutabilis on the First Nature Web site.
Kuehneromyces mutabilis on the MushroomExpert.Com Web site.