Gilled Polypore

Gilled Polypore © SLindner

Birch Mazegill, Multicolor Gill Polypore
Trametes betulina

This shelf-like, fan-shaped mushroom, found on dead hardwood, is notable for its hairy, concentric bands and its unusual true gills on the underside.

Appearance

  • Shelf-like to fan-shaped (2-10 cm. wide)
  • Without a stipe (stem)
  • Upper surface is hairy, with concentric bands of cream, pale-buff, yellow-brown, or grayish-brown
  • Lower surface has white true gills
  • Spore print white
  • Grows scattered to clustered in overlapping shelves

ID Tips

  • Can be confused with turkey-tail (T. versicolor) and conifer mazegill (Gloeophyllum sepiarium)
    • Gilled polypore
      • Upper surface is cream, pale-buff, dingy yellow-brown, or grayish-brown
      • Lower surface has white true gills
      • Grows on dead hardwood (e.g. oaks)
    • Turkey-tail
      • Upper surface is gray, brown, or cream
      • Lower surface has pores
      • Grows on dead hardwood (e.g. oaks)
    • Conifer mazegill
      • Upper surface is rusty-brown
      • Lower surface has brown true gills, often mixed with elongate pores
      • Grows on dead conifers

At Edgewood

About

  • Basidiomycetes – a major lineage of fungi that usually produce spores within basidia (club-like structures)
  • Found from early to late winter
  • Saprotrophic – grows on dead hardwood (e.g. oaks), occasionally on conifers
  • Edibility (San Mateo County Parks prohibits removal of any natural material)
    • Inedible; too tough
    • Unless you are an expert, do not pick and consume wild mushrooms

Fun Facts

  • Gilled polypore belongs to the Polypore family of fungi (Polyporaceae), whose members usually have vertical pores on the underside of their caps
    • As nature always has exceptions, this species has true gills instead!
  • The Polypore family of fungi (Polyporaceae) are typically saprotrophic
    • Identifying the tree they are growing on can help determine the specific species

Learn More

Kuo, M. Oct. 2022. The polypores. MushroomExpert.Com

Roehl, T. 2017, Jul. 14. #013: Characteristics of division Basidiomycota. Fungus Fact List. Fungus Fact Friday.

Roehl, T. 2017, Jul. 7. #030: Mushroom morphology: Polypores. Fungus Fact List. Fungus Fact Friday.

References

Desjardin, D.E., M.G. Wood, and F.A. Stevens. 2016. California Mushrooms: The Comprehensive Identification Guide. Timber Press, Portland, Oregon.

Kuo, M. 2007, Mar. 4. Lenzites betulinus. MushroomExpert.Com.

Wood, M., and F. Stevens. 2024. Trametes betulina. The Fungi of California. MykoWeb.