Boletus edulis Fries
Syst. Mycol. 1: 392. 1821.

Common Name: Porcini, Cepe, King Bolete

• Pileus

  Cap 7-25 cm broad, broadly convex; surface smooth to wrinkled, dry to subviscid in wet weather; color varying from yellow-brown, buff-brown to reddish-brown; flesh thick, white, unchanging; odor and taste mild.

• Hymenophore

  Pores very small, pallid, becoming dull yellow, finally dingy yellowish-green.

• Stipe

  Stipe 7-20 cm long, 3-8 cm thick, equal to clavate, white at the base, brownish above; white reticulations especially at the apex; veil absent.

• Spores

  Spores 12-17 x 4-6 µm, smooth, fusiform to elliptical. Spore print olive-brown.

• Habitat

  In the California, Boletus edulis is associated primarily with pine, particularly Pinus muricata (Bishop Pine), and Pinus radiata (Monterey pine). It fruits sporadically during the spring and summer months (in the latter case from fog drip), with significant fruitings occurring after the first soaking rains of autumn.

• Edibility

  Edible and choice. Buttons are usually prepared fresh while large specimens are typically dried. Like many members of the bolete group, fruiting bodies of Boletus edulis are frequently colonized with fly larva making it difficult sometimes to find edible specimens.

• Comments

  Boletus edulis is distinguished from other members of the bolete group by a combination of characters: substantial size, a smooth to wrinkled brown to reddish-brown cap surface, drab white pores becoming yellowish olive in age, a usually club-shape stipe with distinctive white reticulations at the apex, mild taste, and absence of color changes. A close relative is Boletus regineus (Queen bolete) which differs in having a darker cap with a whitish wash when young, and occurs with mixed hardwoods as opposed to pines.

  Our California taxa has recently been given a new varietal name: Boletus edulis var. grandedulis Arora & Simonini (Economic Botany 62(3): 374).

• References

  Arora, D. (2008). California Porcini: Three New Taxa, Observations on Their Harvest, and the Tragedy of No Commons. Economic Botany 62(3): 356-375.
  Bessette, A.E., Roody, W.C. & Bessette, A.R. (2000). North American Boletes: A Color Guide to the Fleshy Pored Mushrooms. Syracuse University Press: Syracuse, NY. 400 p.
  Smith, A.H. (1949). Mushrooms in their Natural Habitats. Sawyer's Inc: Portland, OR. 626 p.
  Smith, A.H. & Thiers, H.D. (1971). The Boletes of Michigan. University of Michigan Press: Ann Arbor, MI. 426 p.
  Thiers, H. D. (1975). California Mushrooms—A Field Guide to the Boletes. Hafner Press: New York, NY. 261 p. (WWW)

• Other Descriptions and Photos
  • Taylor F. Lockwood: Boletus edulis (CP)
  • Taylor F. Lockwood: Boletus edulis (CP)
  • Taylor F. Lockwood: Boletus edulis (CP)
  • Fred Stevens: Boletus edulis (CP)
  • Fred Stevens: Boletus edulis (CP)
  • Fred Stevens: Boletus edulis (CP)
  • Nathan Wilson: Boletus edulis (CP)
  • Michael Wood: Boletus edulis (CP)
  • Michael Wood: Boletus edulis (CP)
  • Michael Wood: Boletus edulis (CP)
  • Michael Wood: Boletus edulis (CP) -- ready to cook
  • Michael Wood: Boletus edulis (CP) -- double bolete!
  • Boletes of California: Boletus edulis (D & CP)
  • Beverly Hackett: Boletus edulis (I)
  • Beverly Hackett: Boletus edulis (I)
  • Tom Volk's Fungus of the Month: Boletus edulis (D & CP)
  • Boleslaw Kuznik -- Hunting for Mushrooms: Boletus edulis (CP)
  • Mushroom Observer: Boletus edulis (CP)
  • A Few Good Mushrooms: Boletus edulis (D & CP)
  • Eileen's Mushroom Mania: Boletus edulis (CP)
  • Nathan Wilson: Boletus edulis (D & CP)
  • Il Mondo dei Funghi: Boletus edulis (D & CP)
  • Na Grzyby: Boletus edulis (D & CP)
  • Informationszentrale gegen Vergiftungen der Universiteat Bonn: Boletus edulis (D & CP)
  • Sommario funghi: Boletus edulis (D & CP)
  • Svampbok: Boletus edulis (D & CP)
  • Robert Rich: Boletus edulis (D & CP)
  • Pilze, Pilze, Pilze: Boletus edulis (CP)
  • Arora (1986): p. 530, plates 142-144 (CP)
  • Arora (1991): p. 152-158 (D & CP)
  • Bessette et al. (2000): p. 108 (D), p. 290-291 (CP)
  • Breitenbach & Kränzlin (vol. 3): p.54 (D), plate 8 (CP)
  • Fischer & Bessette: p. 95-97 (D), p. 95 (CP)
  • Jordan: p. 337 (D & CP)
  • Lincoff: p. 568 (D), plate 405
  • McKenny et al.: p. 4 (D), p. 5 (CP)
  • Miller: sp. 307 (D & CP)
  • Phillips: p. 233 (D), p. 232-233 (CP)
  • Smith & Weber: sp. 81 (D & CP)
  • Thiers (1975): p. 33-35 (D)
  
  

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