Polyporus squamosus (Huds.) Fr. - Dryad's Saddle

Distribution - Taxonomic History - Etymology - Identification - Culinary Notes - Reference Sources

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Polyporales

Polyporus squamosus, commonly referred to as Dryad's Saddle, grows in overlapping clusters and tiers on broad-leaved trees. (A dryad is a mythical wood-nymph.) The fruit bodies appear in summer and autumn. Insects quickly devour these large brackets, and in warm weather they can decay from full splendour to almost nothing in just a few days.

Sycamore, willow, poplar and walnut trees are all commonly attacked by this impressively large and attractive fungus.

Polyporus squamosus in its less common funnel form

When growing on the trunks of trees this polypore forms brackets that do look rather like saddles; however, they can also occur on fallen trunks and large branches or emerge from the soil where a tree root is just below soil level. In these situations Polyporus squamosus takes on a very different form: a funnel. Some of these funnels are perfect horns; more often they are slightly one sided.

The beautiful funnel-shaped Dryad's Saddles shown on the left were found in woodland in Northumberland quite early in the season even for what is one of the earliest of the annual bracket fungi. The photograph was taken by Bill Stephens, with whose permission they are shown here.

The outer edges of young caps are edible and tender, but mature caps have tough flesh - especially near to the attachment point. Within three or four weeks, Dryad's Saddles become maggot ridden and turn into a smelly mess.

Distribution

Polyporus squamosus is one of the most common of the bracket fungi seen in Britain and Ireland. It occurs across most of mainland Europe and in many parts of Asia and North America.

Taxonomic history

First described scientifically in 1778 by English botanist and apothecary William Hudson (~1730 - 1793), who named it Boletus squamosus, this species was renamed Polyporus squamosus by the great Swedish mycologist Elias Magnus Fries in his Systema Mycologicum of 1821.

Etymology

The generic name Polyporus means 'having many pores', and fungi in this genus do indeed have tubes terminating in pores (usually very small and a lot of them) rather than gills or any other kind of hymenial surface. The specific epithet squamosus means scaly, and in the case of the Dryad's Saddle the cap surface is indeed beautifully patterned with large brown scales.

Identification guide

	Cap Individual caps grow to between 10 and 60cm in diameter and are 5 to 50mm thick. Often in tiers, the caps are attached to the host tree by a very short lateral (occasionally eccentric but not quite lateral) stem that darkens towards the base. Beneath the yellow to tan upper surface, the cap flesh is white and tough.
	Tubes and Pores Irregularly oval tubes 5 to 10mm deep terminate in irregular, angular pores that are white at first but turn cream as the fruiting body matures. The tubes run decurrently on to the short stem.
	Spores Oblong-ellipsoidal, smooth, 10-15 x 4-5.5µm. Spore print White.
Odour/taste	Floury odour and taste.
Habitat	Parasitic on broad-leaf trees.
Season	Spring to late summer or early autumn.
Similar species	Piptoporus betulinus, the Razor Strop Fungus or Birch Polypore, is a similar shape when fully mature, but it is brown on top and white underneath; it is specific to birch trees.

Culinary Notes

I have come across recipes in which this slices of young Dryad's Saddles are fried with bacon and served on hot buttered toast, but I have no first-hand experience of trying these mushrooms. In any case use only young caps, slice them thinly to check that they are maggot free, and cook them thoroughly.

Reference Sources

Mattheck, C., and Weber, K. Manual of Wood Decays in Trees. Arboricultural Association 2003.

Pat O'Reilly, Fascinated by Fungi, 2011.

Dictionary of the Fungi; Paul M. Kirk, Paul F. Cannon, David W. Minter and J. A. Stalpers; CABI, 2008

Taxonomic history and synonym information on these pages is drawn from many sources but in particular from the British Mycological Society's GB Checklist of Fungi and (for basidiomycetes) on Kew's Checklist of the British & Irish Basidiomycota.