Garlic mushroom: Marasmius copelandii
Cap 0.5-2.0 cm broad, convex, expanding to nearly plane at maturity, sometimes slightly umbonate; margin decurved, striate-wrinkled up to two-thirds the distance to the disc; surface more or less glabrous, brown, shading to pale-tan at the margin, in age more uniformly brown, occasionally fading to nearly white; context less than 1 mm thick, colored like the cap; odor of garlic, taste: pungent.
Gill adnate, adnexed, sometimes seceding, thin, close, lamellulae 1-2 seried, cream-buff, darkening to tan-buff.
Stipe 3-8 cm long, 1-3 mm thick, slender, straight, more or less equal, hollow at maturity; surface tomentose, mahogany-brown at the base, tan-buff at the apex; stipe base not instititious; veil absent.
Spores 13-18 x 2.5-3.5 µm, narrowly tear-shaped, smooth, nonamyloid; spore print whitish.
Scattered to gregarious in mixed hardwood-conifer woods; common on leaf duff of oaks (Quercus spp.) and tanbark oak (Lithocarpus densiflora); fruiting from early to mid-winter.
Edible; used as a seasoning according to Arora.
Marasmius copelandii, though small and drab, is not just another little brown mushroom. It's hallmark is a garlic odor so strong that it is frequently found by smell rather than sight. A striate-wrinkled cap, pubescent, two-toned stipe, and preference for oak/tanbark oak leaves, help to distinguish it from other garlic-odored species. Marasmius scorodonius is similar but has a glabrous stipe and fruits on different substrates. According to Desjardin, it is rare in California.