Cerioporus squamosus

Cerioporus squamosus aka Polyporus squamosus is a basidiomycete bracket fungus, with common names including dryad's saddle and pheasant's back mushroom.[2] It has a widespread distribution, being found in North America, Australia, Asia, and Europe, where it causes a white rot in the heartwood of living and dead hardwood trees. The name "dryad's saddle" refers to creatures in Greek mythology called dryads who could conceivably fit and ride on this mushroom, whereas the pheasant's back analogy derives from the pattern of colors on the bracket matching that of a pheasant's back.

Cerioporus squamosus
Polyporus squamosus Molter.jpg
Scientific classification
C. squamosus
Binomial name
Cerioporus squamosus
(Huds.) Quélet (1886)

Polyporus squamosus

Species synonymy[1]
  • Agarico-pulpa ulmi Paulet
  • Boletus cellulosus Lightf.
  • Boletus juglandis Schaeff.
  • Boletus maximus Schumach.
  • Boletus michelii (Fr.) Pollini
  • Boletus polymorphus Bull.
  • Boletus rangiferinus Bolton
  • Boletus squamosus Huds.
  • Bresadolia caucasica Shestunov
  • Bresadolia paradoxa Speg.
  • Bresadolia squamosa (Huds.) Teixeira
  • Cerioporus michelii (Fr.) Quél.
  • Cerioporus rostkowii (Fr.) Quél.
  • Favolus squamosus (Huds.) Ames
  • Melanopus squamosus (Huds.) Pat.
  • Polyporellus rostkowii (Fr.) P. Karst.
  • Polyporellus squamatus (Lloyd) Pilát
  • Polyporellus squamosus (Huds.) P. Karst.
  • Polyporellus squamosus f. rostkowii (Fr.) Pilát
  • Polyporus alpinus Saut.
  • Polyporus caudicinus Murrill
  • Polyporus dissectus Letell.
  • Polyporus flabelliformis Pers.
  • Polyporus flabelliformis Pers.
  • Polyporus infundibuliformis Rostk.
  • Polyporus juglandis (Schaeff.) Pers.
  • Polyporus michelii Fr.
  • Polyporus pallidus Schulzer
  • Polyporus retirugis (Bres.) Ryvarden
  • Polyporus rostkowii Fr.
  • Polyporus squamosus (Huds.) Quél.
  • Polyporus squamatus Lloyd
  • Polyporus squamosus f. michelii (Fr.) Bondartsev
  • Polyporus squamosus f. rostkowii (Fr.) Bondartsev
  • Polyporus squamosus var. maculatus Velen.
  • Polyporus squamosus var. polymorphus (Bull.) P.W. Graff
  • Polyporus ulmi Paulet
  • Polyporus westii Murrill
  • Trametes retirugis Bres.
Cerioporus squamosus
View the Mycomorphbox template that generates the following list
Mycological characteristics
pores on hymenium
cap is depressed or offset
hymenium is decurrent
stipe is bare
spore print is white
ecology is saprotrophic or parasitic
edibility: edible or inedible


The species was first described scientifically by British botanist William Hudson in 1778, who named it Boletus squamosus.[3] It was given its current name in 1886 by Quélet but is still widely known by the Friesian name "Polyporus squamosus".[4]


This mushroom is commonly attached to dead logs or stumps at one point with a thick stem. Generally, the fruit body is 8–30 centimetres (3–12 inches) across and up to 10 cm (4 in) thick. The body can be yellow to brown and has "squamules" or scales on its upper side. On the underside one can see the pores that are characteristic of the genus Cerioporus; they are made up of tubes packed together closely. The tubes are between 1 and 12 mm (132 and 1532 in) long. The stalk is thick and short, up to 5 cm (2 in) long.[2] The fruit body will produce a white spore print if laid onto a sheet of paper. They can be found alone, in clusters of two or three, or forming shelves. Young specimens are soft but toughen with age. It is particularly common on dead elm and is also found on living maple trees.

Distribution and habitatEdit

This organism is common and widespread, being found east of the Rocky Mountains in the United States and over much of Europe. It is also found in Australia and Asia. It commonly fruits in the spring, occasionally during autumn, and rarely during other seasons. Many mushroom hunters will stumble upon this when looking for morels during the spring as both have similar fruiting times, and this fungus can grow to a noticeable size of up to 50 cm (20 in) across.[5] It plays an important role in woodland ecosystems by decomposing wood, usually elm, but is occasionally a parasite on living trees. Other tree hosts include ash, beech, horse chestnut, Persian walnut, lime, maple, planetree, poplar, magnolia, and willow.[6]

Edibility and usesEdit

Edible when young.[7] They can become infested with maggots and become firm, rubbery and inedible as they mature. Cookbooks dealing with preparation generally recommend gathering these while young, slicing them into small pieces and cooking them over a low heat. Some people value the thick, stiff paper that can be made from this and many other mushrooms of the genus Cerioporus. The mushroom's smell resembles watermelon rind.[2] Polyporus squamosus has a mild nutty flavour.



  1. ^ "Species synonymy for Cerioporus squamosus (Huds.) Fr". Species Fungorum. CAB International. Retrieved 2019-09-27.
  2. ^ a b c Spahr DL. (2009). Edible and Medicinal Mushrooms of New England and Eastern Canada. Richmond, Calif: North Atlantic Books. pp. 131–35. ISBN 978-1-55643-795-3. Retrieved 2010-05-28.
  3. ^ Hudson W. (1778). Flora Anglica (2 ed.). p. 626.
  4. ^ Zmitrovich, Ivan V. (2016). "Lentinoid and Polyporoid Fungi, Two Generic Conglomerates Containing Important Medicinal Mushrooms in Molecular Perspective". International Journal of Medicinal Mushrooms. 18 (1): 23–38. doi:10.1615/intjmedmushrooms.v18.i1.40. PMID 27279442. Retrieved 25 May 2016.
  5. ^ Lonsdale D, Butin H. (1995). Tree Diseases and Disorders: Causes, Biology, and Control in Forest and Amenity Trees. Oxford [Oxfordshire]: Oxford University Press. pp. 170–71. ISBN 0-19-854932-6. Retrieved 2010-05-28.
  6. ^ Schmidt O. (2006). Wood and Tree Fungi: Biology, Damage, Protection, and Use. Berlin: Springer. p. 199. ISBN 3-540-32138-1. Retrieved 2010-05-28.
  7. ^ Phillips, Roger (2010). Mushrooms and Other Fungi of North America. Buffalo, NY: Firefly Books. p. 298. ISBN 978-1-55407-651-2.

External linksEdit