Butter Cap

Collybia butyracea

Appears in

By Roger Phillips

Published 2006

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Butter Cap Collybia butyracea (Bull.) P. Kumm. (illustrated 65% life size) Cap 3–7cm across, convex, becoming flattened with a distinct umbo, dark reddish-brown to dark ochraceous-buff, drying horn-brown to ivory; greasy to the touch. Stem 25–50×5–10mm, tough, slightly swollen towards the base; similarly coloured to cap; becoming hollow, base covered in white, woolly hairs. Flesh whitish-buff, taste mushroomy, smell mushroomy or slightly rancid. Gills free, crowded; whitish. Spores 6.5–8×3–3.5¼, elliptical. Spore print white or very pale pink. Habitat in leaf litter in deciduous or coniferous woods; autumn to early winter. Very common. Edible but not good. Note easily recognized by the buttery feel of the cap. A second variety has been mooted, C. butyracea var. asema (Fr.) Quél., and it is possible that this is the form shown here: the cap is said to be generally lighter in colour than the species, beige to greyish-cream. I find cap colour a rather unreliable character, as there is a great deal of variety, which is partly dependent on moisture content and the lateness of the season.