What You Should Know
Clitocybe maxima is aptly named. It is more or less an overgrown version of Infundibulicybe gibba and is treated by some authors as Clitocybe gibba var. maxima. It is identified by its pinkish-tan, centrally depressed cap; its enormous size (caps reaching over 30 cm); its pale gills, which run down the stem; and its range, in the mountains of western North America.
Its fruit body is coming out as a stick, and then differentiated into the cap and stem step by step, so it is also called bamboo shoot mushroom. It is a kind of big-scale agaric. The stem locates in the center of the cap with its epidermis thick and pliable. Its cap is flat to unfold like an umbrella, with gill under it. This mushroom generally occurs in the forest or on the grass from May to October. The fruit body grows single or clusters from the rotten wood or soil.
Other names: Large White Clitocybe, Big Cup mushroom (Dabeixun), Pig Stomach mushroom (Zhudugu), Big Cup Umbrella (Dabeisan) in China.
Clitocybe maxima Mushroom Identification
Saprobic; growing alone or, more frequently, in groups or fairy rings; under hardwoods or conifers; often found in grassy woodland clearings; summer and fall; in the Rocky Mountains and in montane western North America.
8-30 cm (the pocket knife in the illustration is just over 10 cm long!); at first flat or with a central depression, becoming shallowly vase-shaped; dry; smooth; pinkish-tan or slightly darker.
Running down the stem; close; white or tinged pale pinkish.
3-10 cm long; up to 4 cm thick; more or less equal; dry; fairly smooth; whitish, off-white, or a very pale version of the cap color; the base usually covered with white mycelium.
Odor and Taste
Taste not distinctive; odor not distinctive or sweetish-unpleasant.
Spores 6-11 x 5-7 µ; more or less elliptical; smooth; inamyloid. Cystidia absent. Clamp connections are present.
Photo 1 - Author: nschwab (Attribution-NonCommercial 4.0 International)
Photo 2 - Author: nschwab (Attribution-NonCommercial 4.0 International)