Ganoderma applanatum (Persoon) Patouillard
Soc. Mycol. France Bull. 5: 67. 1889.

Photo: The brown spores color the bark and spider web beneath the sporocarp.

Common Name: Artist's Conk

• Sporocarp

  Fruiting body perennial,woody, typically sessile, 6-60 cm broad, 5-10 cm thick, fan-shaped to slightly convex, rarely hoof-like, usually solitary; margin rounded early, becoming narrowed at maturity; surface a hard crust, dull grey, grey-brown to brown, irregular, often furrowed, nodulose and zonate, frequently dusted with brown spores. Flesh up to 6.0 cm thick, brown, tough, corky, blackening in KOH.

• Pores

  Pores 4-6 per mm, white, quickly bruising brown when injured, fading to pale yellowish-buff when dried; tubes multi-seried, 4-13 mm long, brown, each layer separated by a thin layer of tissue; tubes and pores blackening in KOH.

• Spores

  Spores 6-9.5 x 5.7 µm, broadly elliptical, blunt at the distal end, thick-walled, ornamented with minute spines; spores brown in deposit.

• Habitat

  Solitary or in small groups on downed logs of both hardwood and conifers, also on living trees; especially common on Umbellularia californica (California Bay Laurel).

• Edibility

  Inedible, woody.

• Comments

  Our best known shelf fungus, Ganoderma applanatum is distinguished from other woody polypores by a dull grey-brown, bumpy, usually zonate cap, often powdered brown from released spores, and a white pore surface which instantly darkens when injured. The latter feature makes it a favorite of artists which use the smooth white surface as a canvas. Like a number of perennial woody conks, the age of a fruiting body can be roughly determined by sectioning and counting the tube layers. Related fungi include Ganoderma tsugae, uncommon in our area, with a shiny red/brown to mahogany brown cap and pores that do not bruise and Fomitopsis pinicola with a reddish-brown cap margin and pores that bruise slowly pale yellowish-buff. One other Ganoderma that may occur in the S.F. Bay Area is Ganoderma brownii. According to Gilbertson & Ryvarden, it is similar to Ganoderma applanatum but differs in having larger spores and a yellow pore surface.

• Other Descriptions and Photos
  • Nathan Wilson: Artist Conk
  • Michael Wood: Ganoderma applanatum (CP)
  • Michael Wood: Ganoderma applanatum (CP)
  • Michael Wood: Ganoderma applanatum (CP)
  • Michael Wood: Artist conk given to Dr. Harry Thiers, 1986
  • Michael Wood: Artist conk given to Dr. Tom Volk, 2001. Art by Louise Freedman.
  • Boleslaw Kuznik -- Hunting for Mushrooms: Ganoderma applanatum (CP)
  • Common Tree Diseases of British Columbia: Ganoderma applanatum (D & CP)
  • Na Grzyby: Ganoderma applanatum (D & CP)
  • Robert Rich: Ganoderma applanatum (D & CP)
  • Arora (1986): p. 576 (D & P)
  • Arora (1991): p. 194 (D & CP)
  • Breitenbach & Kränzlin (vol. 2): sp. 425 (D, I, & CP)
  • Gilberton & Ryvarden (1986): p. 290 (I), p. 291 (D)
  • Jordan: p. 106 (D & CP)
  • Lincoff: p. 460 (D), plate 518 (CP)
  • Miller: sp. 319 (D)

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