|Major Groups > Gilled Mushrooms > Pale-Spored > Lactarius > Lactarius imperceptus|
by Michael Kuo
Found under oaks in eastern North America, Lactarius imperceptus is a brownish species with white milk that turns yellow when exposed to air . . . in theory. In practice the cap is sometimes rather pinkish, and the yellowing of the milk may be faint (even absent) and/or slow to develop. The cap is never zoned, helping to separate it from other oak-loving species with yellowing milk, like Lactarius chrysorrheus.
Ecology: Mycorrhizal with oaks (especially southern live oaks) and possibly with other hardwoods; summer and fall; widely distributed east of the Great Plains.
Cap: 2.5-9 cm; convex, with an incurved margin when young, becoming flat or shallowly depressed, often with a central bump; dry or moist; bald; dull brown to tan, cinnamon tan, pinkish brown, or paler; consistently without zones of color or texture.
Gills: Attached to the stem or beginning to run down it; close; whitish to pinkish or very pale tan; often developing cinnamon to reddish brown stains and discolorations.
Stem: 2.5-9 cm long; up to about 1.5 cm thick; more or less equal; dry or moist; without potholes; smooth; pale at first, becoming colored like the cap.
Flesh: Thin; pale, becoming pinkish; not changing when sliced, or turning slowly yellowish to yellow.
Milk: Creamy; turning slightly to substantially yellowish (often very slowly) or not yellowing appreciably; not staining tissues, or staining them yellowish; staining white paper yellow.
Odor and Taste: Odor not distinctive; taste usually acrid but sometimes weakly so.
Spore Print: White to yellowish.
Microscopic Features: Spores 7-9.5 x 6-8 µ; broadly ellipsoid; ornamentation 0.5-1.5 µ high, as amyloid warts and ridges that form broken reticula or remain scattered. Pleuromacrocystidia to about 70 x 10 µ; fusiform to fusoid-mucronate or subcylindric, often with an apical constriction. Cheilomacrocystidia similar but shorter. Pileipellis an ixolattice or ixotrichoderm, with the gelatinous material quickly dissolving in KOH mounts.
This site contains no information about the edibility or toxicity of mushrooms.
Cite this page as:
Kuo, M. (2011, March). Lactarius imperceptus. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/lactarius_imperceptus.html