Fruiting body 2-6 cm tall, 2-4 cm broad, erect-cupulate, blunt to truncate in profile, split down one side, tapering below, substipitate, or the stipe lacking; margin wavy to contorted when fruiting in clusters; hymenial surface pale-dull-brown to light-greyish-brown; exterior surface light-brown, finely pubescent to nearly glabrous; context up to 2 mm thick, pliant, pallid; odor and taste mild.
Spores 14-15.5 x 7-8 µm, elliptical, smooth, with two oil droplets; asci non-amyloid; paraphysis hooked.
Typically clustered, but occasionally solitary, in mixed hardwood/conifer woods; fruiting from late fall to mid-winter.
Otidea alutacea can be separated from other California Otideas by shape (cups blunt in profile rather than elongated), a brownish to brownish-grey hymenium, and clustered fruiting habit. It is fairly common in our woodlands but often overlooked. A close relative, Otidea alutacea var. microspora, has a more yellowish exterior and as the name suggests, smaller spores. Two other Otidea species which may be encountered include O. leporina, with a more tapered cup and yellowish-brown hymenium, and O. onotica, larger than the latter, ear-like in shape, the hymenium yellowish-brown, often with pinkish tints.