Fried Chicken Mushroom

The caps are smooth, varied in color, and range from 4–12 cm (1+1⁄2–4+3⁄4 in) wide. The whitish-grayish stalks are 5–10 cm (2–4 in) long and 1–3 cm (3⁄8–1+1⁄8 in) wide. The gills are white but may yellow slightly with age. The firm flesh remains white on exposure. The spores are white.

Similar species. Lyophyllum semitale and Pluteus petasatus are similar in appearance, as is L. fumosum; it and L. loricatum are sometimes grouped with L. decastes as a species complex, lacking distinct differentiating features.

The species was originally described from Sweden and is widespread throughout Europe and north temperate regions. It is prolific in summer and fall until spring on the West Coast of the United States and is widely distributed in North America. It also occurs in eastern temperate Asia. Growing in dense, often huge clusters on the ground, the mushrooms are usually found where the ground has been disturbed such as roadbeds, gravel, paths, landscaping areas, and sometimes in woods. It is variously considered saprotrophic or ectomycorrhizal.

In North America, the species is considered edible and occasionally collected in the wild, but there are some reports of gastric upset and possible confusion with poisonous Entoloma species or Clitocybe dilatata. The species is commercially cultivated in Japan, where it is known as hatake shimeji, and in China, where it is known as luronggu. The fungus is considered to be both a food and a health supplement and is grown on sawdust or bark compost.