Kuehneromyces mutabilis, also known as Sheathed Woodtuft, is a medium-sized agaric that has a bright tan cap which becomes paler from the centre when drying. 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, favoring 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. 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 A group of poisonous Galerina species are similar. Galerina are unicolor and Galerina marginata have fibers and no stem scales.

Warning: This mushroom is not recommended to be picked as food because it can be confused with the deadly poisonous Galerina marginata.

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