Lactarius tabidus
Description
Lactarius tabidus is an inedible mushroom of the genus Lactarius. It is a small mushroom with an orange-brown cap, cinnamon gills that exudes white milk. It grows solitary or in scattered groups on soil under broad-leaf trees, favoring birch. The milk has a bitter and acrid taste, with a slightly hot aftertaste. The fact that the white milk dries yellow is an indicator that it may be poisonous.
This mushroom can be found under a pine in autumn. It is common in southern Britain, becoming rarer northwards. It can also be found in North America. It grows best in leaf litter or Sphagnum moss.
Common names: Birch Milkcap.
Mushroom Identification
Cap
Convex at first, then flattening or becoming slightly funnel-shaped, often with a shallow, narrow umbo; 2 to 4.5cm in diameter, the yellowish-brown to orange-brown caps, darkest towards the center, are slightly hygrophanous and turn more ochre from the margin when old and dry.
Caps have finely matt and wrinkled surfaces, and old specimens are often visibly crenulate at the margin.
Gills
The gills, which are pale cinnamon with a pinkish tinge, are weakly decurrent and crowded. As they mature, the gills tend to become blotchy.
When the gills of this milkcap is damaged, a white latex is released; its taste is initially mild but later becomes acrid. On a white handkerchief or tissue the latex leaves a damp mark that slowly turns yellow.
Stem
Solid at first, eventually becoming hollow; 5 to 10mm in diameter and 3 to 7cm tall, the cylindrical or slightly upward-tapering stem is rather brittle; its surface is smooth and much the same color as the cap, a little paler towards the apex and darker towards the base. The stem flesh is whitish; there is no stem ring.
Spores
Broadly ellipsoidal, 7-9 x 6-7μm, hyaline; ornamented with many pointed warts up to 1.2μm in height, mostly isolated but with just a few linking ridges.
Spore Print
Pale cream with a slight salmon pink tinge.
Odor and Taste
No distinctive odor; initially a mild taste that gradually becomes acrider.
Habitat & Ecological Role
Ectomycorrhizal with hardwood trees, notably birches; in damp and often mossy woodlands.
Similar Species
Lactarius subdulcis is of similar coloration; it occurs mostly under beech trees.
History
In 1838 Swedish mycologist Elias Magnus Fries established 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 tabidus include Lactarius subdulcis, Lactarius theiogalus, Lactarius chrysorheus, Lactarius hepaticus.
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 tabidus is a Latin adjective that translates as 'stunted' - a reference to the small size of these milkcaps in comparison with many other members of the Lactarius genus.
Photo sources:
Photo 1 - Author: Jerzy Opioła (CC BY-SA 3.0)
Photo 2 - Author: Jerzy Opioła (CC BY-SA 3.0)
Photo 3 - Author: Jerzy Opioła (CC BY-SA 3.0)
Photo 4 - Author: Jerzy Opioła (CC BY-SA 4.0)
Photo 5 - Author: Jerzy Opioła (CC BY-SA 4.0)
