Russula mordax — Biting russula
Biting russula3, photograph by Adolf Ceska.
Biting russula7, showing colour variation in caps and stems, photograph by Benjamin Woo with permission from University of Washington, Burke Museum.
Biting russula8 photograph by Benjamin Woo with permission from University of Washington, Burke Museum.
Biting russula9 photograph by Benjamin Woo with permission from University of Washington, Burke Museum.
Biting russula3 sliced to show gills, flesh. Photograph by Adolf Ceska.
Biting russula10 sketches and spore measurements by Benjamin Woo with permission from University of Washington, Burke Museum.
Odour: None or banal.
Taste: Gills and flesh usually hot or 'biting', (taste a pea-sized portion, then spit it out) giving the species its Latin and common names.
Cap: 5–13 cm in diameter, rounded convex when young, later flattening out, but keeping the rounded margin. The centre is depressed. The colour of young specimens is yellowish with brown, and becomes brownish red, copper-red-brown or more orange or with peach tinges. Some specimens have a yellow cap with a pink rim. The margin is not grooved or is only slightly grooved in fully expanded caps. The surface is dry or slightly viscid in wet weather. The mushrooms are firm.
Gills: Crowded to medium-spaced, cream to yellow-cream. Few if any short gills present, but the gills can be forked near the stem.
Stem: 5–13 cm long x 1–3 cm wide, cylindrical, white with pinkish blush or tint, except for the very top. Not staining when scratched or rubbed. Firm.
Ring or veil: None.
Cup: None.
Spores: 7.5–9 x 6.5–7 µm, with low scattered warts forming a network on the spore surface.
Habitat: On soil, in various conifer forests, reported with Douglas fir (Pseudotsuga menziesii), and western hemlock (Tsuga heterophylla). Common and widespread. Ectomycorrhizal.
Geographical distribution: BC and Pacific northwest.
The biting russula is one of the most common species in the Pacific northwest but recognizing it as such requires comparison of DNA barcode sequences. Of 715 of the specimens collected by Benjamin Woo and sequenced by Anna Bazzicalupo, almost a tenth turned out to be the biting russulas. A Russula specimen collected in Washington (probably also Oregon and BC) of robust size with thick, acrid/hot flesh and cream to yellow gills has a high probability of being a biting russula. However, biting russula specimens vary greatly in cap and stem colours and microscopic or even molecular characteristics are sometimes necessary to distinguish them from similar species.
Treatment: Contact your regional Poison Control Centre if you or someone you know is ill after eating wild 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.