Lactarius rufus
Description
Lactarius rufus is a common, medium-sized member of the mushroom genus Lactarius It is dark brick red, and grows with pine or birch trees. The flesh tastes very hot after about 30 seconds but can be eaten only after being salted and then pickled.
According to David Arora the Rufous Milkcap has been harvested commercially in Scandinavia and Russia for many years, most western field guides and other sources of culinary guidance - Class this as an inedible mushroom. It is sometimes dried and powdered (after thorough cooking) for use as a seasoning.
Lactarius rufus is similar to Lactarius rufulus, but the latter has a faintly acrid taste, is associated with oaks, has globose spores, and lacks sphaerocysts in the cap and stipe context. Faded specimens of L. rufus are similar to darker individuals of Lactarius xanthogalactus, but that species is easy to distinguish by its typically zonate cap and its latex, which turns quickly yellow upon exposure.
Common names: Rufous Milkcap, Red Hot Milk Cap.
Mushroom Identification
Cap
4 to 10 cm in diameter, the dark reddish-brown caps are dry and have a finely matt surface; slightly sticky in wet weather. Convex at first, the caps become funnel-shaped as the fruiting body matures. There is often a small central umbo once the cap has expanded and become funnel-shaped.
Gills
The pale reddish-cream gills are weakly decurrent and crowded. As they mature, the gills tend to become blotchy.
When the gills of this milkcap is damaged, a watery-white latex is released; its taste is initially mild but later becomes very hot and acrid.
Stem
5 to 20 mm in diameter and 4 to 9cm tall, the stems are smooth and the same color as the cap or a little paler. There is no stem ring.
Spores
Broadly ellipsoidal, 6.5-9 x 5.5-6.5μm, hyaline; ornamented with a well-developed and almost complete network of ridges.
Spore Print
Pale cream with a slight salmon pink tinge.
Odor and Taste
No distinctive odor but a mild taste that soon becomes very hot and acrid.
Habitat & Ecological Role
Coniferous woodland, usually under pines; occasionally under birches.
Similar Species
Lactarius subdulcis is a smaller milkcap sometimes of similar coloration; it occurs under beech trees.
History
The Rufous Milkcap was described in 1772 by Tyrolean mycologist Giovanni Antonio Scopoli (1723 - 1788), who established the basionym of this species when he gave it the scientific name Agaricus rufus.
In 1838 the Swedish mycologist Elias Magnus Fries transferred this milkcap to the genus Lactarius, thereby establishing its scientific name as Lactarius rufus, which is still the binomial name by which it is generally referred to by mycologists today.
Synonyms of Lactarius rufus include Agaricus rufus Scop., Lactarius rufus var. exumbonatus Boud., and Lactarius mollis D.A. Reid.
The generic name Lactarius means producing milk (lactating) - a reference to the milky latex that is exuded from the gills of milkcap fungi when they are cut or torn.
The specific epithet rufus is a Latin adjective that translates as rufous, meaning a foxy reddish-brown color.
Photo sources:
Photo 1 - Author: (Photo by E. Barge) Barge EG, Cripps CL (2016) New reports, phylogenetic analysis, and a key to Lactarius Pers. in the Greater Yellowstone Ecosystem informed by molecular data. MycoKeys 15: 1-58. https://doi.org/10.3897/mycokeys.15.9587 (CC BY-SA 4.0)
Photo 2 - Author: Jerzy Opioła (CC BY-SA 3.0)
Photo 3 - Author: Zonda Grattus, aka Luridiformis at en.wikipedia (the sole owner and copyright holder of this image) (CC BY 3.0)
Photo 4 - Author: Andreas Kunze (CC BY-SA 3.0)