Midwest

American

Mycological

Information

Hydnum repandum, Hydnum rufescens,
and other Hydnum species

Hydnum repandum

Hydnum repandum

Hydnum rufescens

Hydnum rufescens

Common name: Hedgehog mushroom, Sweet tooth.

Description: Hedgehogs mushrooms are colored like pale peaches (whitish to buff to pale orange to pale reddish orange). and are some of the few species of mushrooms that have small spines (also called teeth—see picture below) under their caps instead of gills or pores. The spines/teeth are the spore-bearing surfaces of these mushrooms.

Hedgehogs grow in both hardwoods and conifers. They can be found growing singly, in small clumps, or gregariously in large troops on forest floors. All species of hedgehogs are choice edibles. Some claim H. rufescens, which has a slightly darker and more reddish cap than H. repandum, has the best flavor. An older name for the genus is Dentinum, in reference to the tooth-like, spore-bearing structure.

Spines of Hydnumb

Spines / teeth of H. repandum

The peach-colored caps of Hydnum species are broadly convex, with a wavy or deeply indented margin. They ranges in size from ¾ to 7 inches (2 to 17 cm.) wide in most species, with specimens of the lighter colored H. albomagnum reaching 12 inches wide (30 cm.). H. repandum and its relatives have a dark-orange, bruising reaction when young, but this diminishes as the caps age. The whitish-to-yellowish-to-pale-orange spines under the cap are 1/16 to ¼ inches (2 to 7 mm.) long, and also bruise to a darker orange. The white or cap-colored stem is 1 to 4 inches (2.5 to 10 cm.) tall, with a diameter of 1/3 to 1 ½ inches (1 to 4 cm.) thick. The firm, brittle, white flesh has a mild odor, and a mild to peppery taste. The spore print is white.

Hydnum species are among a very few species of mushrooms with spines as the hymenium (spore-bearing surface). Other species occur in the genus Sarcodon, none of which are choice edibles, and none of which have the light peachy coloration of the Hydnums and Hydnellums which are generally too woody to eat and which have much smaller spines and much thicker stems in relationship to cap size than Hydnums.

Ecology/associated hosts: Hydnum species are mycorhizzal mushrooms (in a symbiotic relationship with the roots of certain trees). Interestingly, Hydnums can form this relationship with both hardwoods and conifers. In Midwest America, Hydnums fruit from July to October, though they are more common in the summer. There is a smaller edible relative, Hydnum umbilicatum, with a centrally depressed cap, which grows in swampy spruce, balsam or cedar woods.

Hydnum umbilicatum

Hydnum umbilicatum

Sarcodon imbricatus

Sarcodon imbricatus

Poisonous look-alikes:There are no poisonous look-alikes. The other mushrooms with caps and stems and spines, such as Sarcondon imbricatus (above) are generally not edible because of texture (leathery) or taste (bitter).

Tips on harvesting: Individual mushrooms are best harvested by cutting them off just above the ground. Be especially careful not to get dirt into the spine area, as cleaning the spines can be quite tedious. Specimens are best cleaned by brushing away dirt with a mushroom brush.

Special considerations for cooking: Generally, these mushrooms should be cooked slowly and at length to make them tender. They are excellent in casseroles, tomato sauces, and braised with sour cream. They are also good just sautéed in butter or olive oil with garlic, but it is recommended to remove the spines as they may start to burn before the main body of the mushroom begins to brown.

Possible allergic reactions: There are no reported problems with Hydnum repandum and its relatives. Take the same precautions that are recommended for all edible, wild mushrooms: cook them well, eat only a small amount the first time you try them. Some people have had allergic reactions to the store-brought white button mushroom, so precaution is always recommended when trying any mushroom for the first time. Do not try more than one new species of mushroom at the same time.

Special considerations for storage: Fresh Hydnums, like all mushrooms, need to be stored in containers that are not air-tight. Paper bags, waxed paper bags or waxed paper are preferable to any plastic containers or bags.

For long term storage, it is best to partially sauté these mushroom and then freeze them. It is not recommended to dry them, as dried hedgehogs do not reconstitute very well, and can be somewhat leathery.

Photos:

Hydnellum compactum

Hydnellum compactum

Hydnellum aurantiacum

Hydnellum aurantiacum

Young Hydnum repandum

Young Hydnum repandum

Old Hydnum repandum

Old Hydnum repandum

H. repandum with primordia

H. repandum with primordia

Darker H. repandu

Darker H. repandu

References:

Arora, David (1979, 1986) Mushrooms Demystified, Ten Speed Press, pp. 618-19.

Kuo, Michael (August 2002) Hydnum repandum .

Kuo, Michael and Methven, Andrew S. ( 2014) Mushrooms of the Midwest, University of Illinois Press p 210.

Lincoff, Gary (1981) National Audubon Society Field Guide to North American Mushrooms, Alfred A. Knopf, p. 428, plate 455.

Michigan Mushroom Hunters Club, August 2009 Mushroom of the Month/

Roberts, Peter and Evans, Shelley (2011) The Book of Fungi, University of Chicago Press, p471.

Volk, Tom, Tom Volk's Fungus of the Month for October 2004.

Mycoweb (California description, but lots of links to other sites)