Cerioporus squamosus

by Barbora Batokova • May 16, 2021

This polypore was the first mushroom I ever found in Frick Park when I started to photograph mushrooms in Pennsylvania. It is an annual polypore that grows in the spring on hardwood trees and stumps, often found during morel season. Many people don’t consider it worthy for the kitchen, but if you find it young, it can be quite delicious! You can easily recognize it by its semicircular shape, the brown scales arranged in a circular pattern, and its smell reminiscent of cucumbers or watermelon. They are often visible from far away as they can grow quite large—up to 2 ft across sometimes!¹

It is known by three common names. First is dryad's saddle which has one of the coolest back stories. It refers to the mushroom shape and creatures in Greek mythology called dryads, who are tree nymphs or tree spirits that could apparently fit and ride on this mushroom! The other two names, pheasant’s back and hawk’s wing, reference the pattern created by the brown scales on the cap of the mushroom that resembles the back of a female pheasant or the wing of a hawk.

Etymology
Taxonomic History
Ecology
Description
Distribution
Similar Species
Edibility and Taste
Cuisine
Medicinal Properties
ID Table

Etymology

The specific epithet squamosus refers to the brown squamules (scales), meaning "scaly." I couldn’t find the full meaning of Cerioporus but it references “pores.”

Taxonomic History

The species was first known as Boletus squamosus, as named by the British botanist William Hudson, who first scientifically described it in 1778. In 1821, Fries transferred it to Polyporus in his Systema Mycologicum. In 1886 Quélet put it into Cerioporus, which is the currently accepted name; however, it has also been widely known by the Friesian name.

Ecology

The dryad’s saddle polypore often grows on fallen, barkless hardwood logs. Thanks to its size, you can spot it from far away.

The polypore is saprobic on decaying hardwood logs and stumps as well as parasitic on living hardwoods, causing a white rot. Michael Kuo reports that it is especially fond of silver maple and box elder in eastern North America and quaking aspen in western North America. In Europe, it likes to grow on lindens, maples, ash trees, walnut trees, willows, and beeches. It grows singly or in overlapping clusters.

Description

When young, the polypore resembles bottle stoppers. As it matures, it develops into a kidney-shaped fruitbody with a thick black stem.

This mushroom is a shelf fungus that starts off as a stubby little knob that will develop into a pale beige semicircular (or kidney-shaped) cap covered with brown, feathery scales, or squamules, that are radially arranged. The cap is usually around 10 cm wide but can grow up to 60 cm. As the mushroom matures, the scales darken, and the edges of the cap can split. It is attached to the substrate by a thick lateral stem that is white with pores running down it first, but becoming dark and velvety with age. The underside is whitish to creamy, becoming yellowish with old age. The pores are small and barely visible at first, but get larger as the mushroom ages, becoming angular and irregular. The pores or flesh does not change when bruised. The white flesh is soft when young, but gets corky with age.

Distribution

Some of the primary characteristics of this polypore are pores running down the stem and brown scales on the cap that are arranged in a circular pattern. As it matures, the edges of the fruitbody can split.

This polypore is common and widespread east of the Rocky Mountains in the United States and much of Europe. However, it can also be found in western North America, Australia, and Asia. It commonly fruits in the spring, and occasionally during autumn.

Similar Species

This polypore doesn’t have any close lookalikes, but Polyporus tuberaster may look similar. It grows on the west coast of the United States and across most of mainland Europe, infrequently in Britain and Ireland, and in parts of Asia. It also has an ochre scaly cap, but grows from a large, black, tuberlike structure and is round rather than kidney-shaped.

Various guides also mention Polyporus fagicola (Polyporus lentus), which is smaller, less scaly, and has smaller pores, and yellowish-white stalk with hairy base.³ In California, there is Polyporus mcmurphyi, which has smaller pores and whitish stalk.

Edibility and Taste

This specimen is good to eat—it’s small and pores are barely visible.

Young specimens are edible, but it can be tricky to find them at the right time. The best way to tell is by the size, the color fo the stem, and the size of their pores.

Good to eat:

cap is smaller than 10 cm
stem is still white with pores running down it
pores are small and can be easily scraped off with a knife

Too old to eat:

cap is usually larger than 10 cm
stem is black
pores are large and the tube layer is thick

These specimens are too old to eat. Even though the one on the left is fairly small, the large pores indicate it is old. The specimens on the right are large, which also indicates age.

However, small specimens don’t always equate to young specimens, so make sure you check the stem and pores as well. Either leave it behind for the dryads to ride, or take it home to make a delicious mushroom broth.

They have a mildly nutty taste (the cucumber or watermelon odor disappears with cooking) and a crunchy texture.

Cuisine

Young dryad’s saddle can be pickled, sautéd or fried. Older specimens can be used to make excellent mushrooms stock. I’ve used the young and soft flesh and the mushroom stock to make Dryad’s Saddle Soup.

The one thing all the dryad’s saddle recipes have in common is to slice this mushroom very thin. Then you can use it like any other mushroom. The key is to work with young specimens, because old ones are too tough to be good to eat. I think it’s best sautéd in butter until almost crispy—that’s when it develops its flavor best. I have also used in a mushroom soup. Older specimens make a great mushroom broth—just toss it with some garlic cloves and wild spices (3 all spice, 3 whole peppercorns, 1 bay leaf) and simmer for 3 hours. Czech sources recommend to prepare it as breaded and fried mushroom escalopes (řízky), make a fake tripe soup (dršťková polévka), or fake cooked pig’s ear (ovar).⁴ I have also come across a source claiming recipes for cooking dryad's saddle were recorded in Transylvania dating back to the 17^th century.

Medicinal Properties

Research on this subject is scarce and just beginning, but a 2018 study from Romania has found the mushroom has significant antioxidant and antimicrobial properties and that it might be further explored as a medicinal mushroom to create different pharmaceuticals as well as a dietary supplement.⁵

ID Table

	Scientific Name	Cerioporus squamosus (Polyporus squamosus)
	Common Name	Dryad’s Saddle, Pheasant’s Back, Hawk’s Wing
	Edibility	Edible
	Ecology	Saprobic and parasitic
	Grows with	Hardwoods
	Distribution	North America, Asia, Europe
	Cap	Kidney-shaped • 10-30cm • Scaly • Whitish to ochre
	Hymenium	Pores • Angular • White
	Stipe	Stublike • 1-5 cm • Thickness • White, then black
	Flesh	White • Not bruising
	Odor & Taste	Resembling cucumbers or watermelon • Mildly nutty
	Spore Print	White