Pleurotus ostreatus (Jacq.) Quélet
Champ. Jura. Vosg. 1: 112. 1872.

Common Name: Oyster Mushroom

• Pileus

  Cap 5-25 cm broad, fan-shaped, broadly convex to sometimes nearly plane at maturity; margin lobed to wavy, especially when young; surface smooth, white to greyish-brown; flesh white, odor of anise.

• Lamellae

  Gills decurrent, white, yellowish in age; veil absent.

• Stipe

  Stipe often absent, when present, short and thick: 0.5-3.0 cm long, 0.5-2.0 cm thick, eccentric or lateral with dense white hairs at the base.

• Spores

  Spores 7.5-9 x 3.5-4.5 µm, smooth, elliptical, nonamyloid. Spore print white.

• Habitat

  Forming overlapping shelves or clusters on stumps and logs of hardwoods, uncommon on conifers, from early fall to mid- winter. Pleurotus ostreatus is a member of the "Fog Flora" fruiting sporadically along the coast during the summer.

• Edibility

  Edible and very popular, although a few people are allergic to it.

• Comments

  Pleurotus ostreatus is believed to be a species complex. In the S.F. Bay Area, specimens can be found that vary from white and relatively thin-fleshed on oaks to thick fleshed, grey-brown shelves on cottonwood and willow. Whether these differences are environmentally induced or genetic is not clear, but most mycophagists prefer the large, thick-fleshed specimens collected from cottonwood.

• Other Descriptions and Photos
  • Brother Alfred Brousseau: Pleurotus ostreatus (CP)
  • Tom Duffy: Pleurotus ostreatus (CP)
  • Terry Goyan: Pleurotus ostreatus (CP) -- closeup of the gills
  • Boleslaw Kuznik: Pleurotus ostreatus (CP)
  • Boleslaw Kuznik: Pleurotus ostreatus (CP)
  • Robert Mackler: Pleurotus ostreatus (CP)
  • Fred Stevens: Pleurotus ostreatus (CP)
  • Michael Wood: Pleurotus ostreatus (CP)
  • Michael Wood: Pleurotus ostreatus (CP)
  • Boleslaw Kuznik -- Hunting for Mushrooms: Pleurotus ostreatus (CP)
  • Tom Volk's Fungus of the Month: Pleurotus ostreatus (D & CP)
  • A Few Good Mushrooms: Pleurotus ostreatus (D & CP)
  • Associació Micològica Joaquim Codina: Pleurotus ostreatus (D & CP)
  • Eileen's Mushroom Mania: Pleurotus ostreatus (CP)
  • Na Grzyby: Pleurotus ostreatus (D & CP)
  • Elias Fries' fungus plates: Pleurotus ostreatus (I) [Agaricus ostreatus]
  • R. A. Chilton: Pleurotus ostreatus (CP)
  • Robert Rich: Pleurotus ostreatus (D & CP)
  • Pilze, Pilze, Pilze: Pleurotus ostreatus (CP)
  • Kinok-ya: Pleurotus ostreatus (CP)
  • Arora (1986): p. 134 (D), p. 135 (P), plates 27, 28 (CP)
  • Arora (1991): p. 35 (D & CP)
  • Breitenbach & Kränzlin (v. 3): sp. 397 (D, I, & CP)
  • Fischer & Bessette: p. 87 (D), p. 88, 89 (CP)
  • Jordan: p. 331 (D & CP)
  • Lincoff: p. 793 (D), plates 484, 497 (CP)
  • McKenny et al.: p. 94 (D & CP)
  • Miller: sp. 93 (D & CP)
  • Phillips: p. 206 (D & CP)
  • Smith: sp. 81 (D & CP)
  • Smith & Weber: sp. 140 (D & CP)
  
  

  (D=Description; I=Illustration; P=Photo; CP=Color Photo)