Shaggy mane

Identity

Shaggy mane is the common name for Coprinus comatus, a mushroom that grows in groups on lawns, gardens, cemeteries and disturbed ground. The British Columbia guide describes a cap 2.5 to 7 cm wide and 5 to 20 cm tall, cylindrical when young and expanding flat with a rolled-up margin. It is white with flat light-brown scales and a brown patch on top. The gills are very crowded and white at first, then pink and finally black. The stem is hollow with a small movable ring.

Edibility and timing

The UBC guide says that young specimens are eaten, and that they should be consumed as soon as possible after collection, before they turn black. As the mushroom matures the gills self-destruct into a black ink that carries the spores, a process known as autolysis. The guide gives no cooking method and no storage advice beyond eating the mushroom quickly.

Lookalikes and contamination

The common inky cap, Coprinopsis atramentaria, is shorter, usually under 8 cm, grey to brown, smooth and without scales. It contains coprine, which causes a reaction with alcohol, so it should not be eaten with alcohol before or after. The green-gill parasol, Chlorophyllum molybdites, is poisonous; its cap margin does not roll up and its gills do not liquefy.

The guide advises against eating mushrooms from disturbed or contaminated soil, because they can accumulate mercury and other heavy metals.

Safety record

The UBC guide says shaggy mane has no known human toxins but has been linked to some cases of gastrointestinal upset, some of which may have involved misidentified inky caps or green-gill parasols. The catalogue's caution is that the species is very perishable and must not be merged with the alcohol-reactive inky cap. The sources read do not establish whether alcohol affects shaggy mane itself, and this page makes no claim on that point.