Hydnum washingtonianum — American hedgehog mushroom

Card image cap

Hedgehog mushroom2, photograph by Ludovic Le Renard.

Hedgehog mushrooms7, photograph by Adolf Ceska.

Edible and sought after

Gills: None; white, cream to apricot spines
Spore print: White


Odour: Fruity to indistinct. When raw (nibble, taste, spit out) a bit acrid or bitter.
Cap: 3–15 cm in diameter. The cap shape is initially rounded and sometimes creased or irregularly crumpled, flattening with age. The margin is rolled inwards towards the stem. The surface is a pale pinkish-orange cream colour, staining ochre when damaged. The matt surface is characteristic. The flesh is thick and white, a bit brittle in the cap. White-capped specimens occasionally occur as well.
Spines: Densely set on the underside of the cap and the upper part of the stem. They are up to 1 cm long, cream to pale apricot-coloured, and they break off easily.
Stem: 2–10 cm long x 1 –4 cm wide, often widest just above the base. White, but staining ochre when damaged. The stem is solid, and firm.
Ring or veil: None.
Cup: None.
Spores: 8–9 x 6–7 µm, smooth.
Habitat: On the ground in Sitka spruce (Picea sitchensis) and mixed conifer forests; ectomycorrhizal.
Geographic distribution: Hydnum washingtonianum, the American hedgehog, is known only from North America5,6. Earlier, the American hedgehog has been lumped with European and Asian species in "Hydnum repandum". Additional endemic Pacific northwest and BC species remain to be described.

When verifying that a mushroom is a hedgehog, make sure that it has pale spines rather than pores or flattened gills on the underside of its cap. A distinct stem and tender flesh (as opposed to rubbery or tough flesh) help set the hedgehog apart from other tooth fungi. The edible but flavourless jelly fungi known variously as 'jelly hogs', 'cat's tongue', or 'spirit gummy bears' (Pseudohydnum gelatinosum) also have spines but they are rubbery rather than brittle and their spines do not rub off.

The bellybutton hedgehog mushroom (Hydnum umbilicatum) is a related, smaller species with a deep depression in the centre of its cap. Its relatively long spines are attached only on the underside of the cap and not at the top of the stem.

All hedgehog mushrooms are prized as good edibles and commercially sold. Hydnum is closely related to chanterelles (Cantharellus). Hydnum repandum as seen from the top, resembles a chanterelle.

Treatment: Individual reactions vary even to species that are generally regarded as edible. Contact your Poison Control Centre if you or someone you know becomes ill after eating hedgehog mushrooms. Poison centres provide free, expert medical advice 24 hours a day, seven days a week. If possible, save the mushrooms or some of the leftover food containing the mushrooms to help confirm identification.

Poison Control:
British Columbia: 604-682-5050 or 1-800-567-8911.
United States (WA, OR, ID): 1-800-222-1222.

1
MyCoPortal. Mycology Collections Portal, <http://mycoportal.org/portal/collections/harvestparams.php> accessed February 2018.
2
Specimen Hydnum washingtonianum UBC F32062 MO 181346, GenBank #MF954988.
3
Siegel, N. & Schwarz, C. Mushrooms of the Redwood Coast. A Comprehensive Guide to the Fungi of Coastal Northern California. Ten Speed Press, Berkeley, California (2016).
4
Trudell, S., Ammirati, J. F. & Mello, M. Mushrooms of the Pacific Northwest. Timber Press, Portland, Oregon (2009).
5
Niskanen, T. et al. Identifying and naming the currently known diversity of the genus Hydnum with an emphasis on European and North American taxa. Mycologia, null-null, doi:10.1080/00275514.2018.1477004 (2018).
6
Swenie, R. A., Baroni, T. J. & Matheny, P. B. Six new species and reports of Hydnum (Cantharellales) from eastern North America. MycoKeys 42, 35-72 (2018).
7
Specimen Hydnum repandum UBC F30514 MO 77980.