A large, pale gray to ivory pink-spored mushroom of broadleaf woods and one of the most frequent causes of mushroom poisoning in Europe. It is POISONOUS, causing severe and sometimes prolonged gastrointestinal illness. Its pale cap, notched yellowish gills that turn pink, and lack of a ring let it pass for several edible species, including the St George's mushroom, the miller and young field mushrooms.
POISONOUS; do not eat. Causes severe gastrointestinal poisoning (vomiting, diarrhea, abdominal pain, headache) 30 minutes to 2 hours after eating, lasting up to 48 hours; liver injury and mood disturbance have been reported, and at least one source reports deaths. The toxin is unidentified (gastrointestinal irritant). Often mistaken for St George's mushroom, the miller, clouded agaric or Agaricus; reject any pale, ringless gilled mushroom with pinkish gills or a pink spore print.
Never eat a wild mushroom based on a web page — confirm with an expert.
Habitat
Mostly in deciduous woodland, especially under oak and beech, less often birch, typically on clay or calcareous soils; sometimes in nearby parks and grassy areas. Grows singly or in groups, sometimes in rings. Reported to form ectomycorrhizae with willow. Late summer and autumn in Europe; summer and autumn in North America.
Distribution
Throughout Europe, more common in the south and center than the northwest; reported from western Asia (Turkey, Iran) and China (Yunnan). Wikipedia describes it as fairly common and widespread in North America, but the sources consulted do not say whether North American collections have been confirmed as the same species as European material.
Characteristics
Cap: 6-15 cm or more, conical to convex, becoming flat with a broad blunt umbo; ivory to pale grayish or grayish brown, darkening with age; slightly sticky when young, margin often wavy or lobed. Gills: notched (sinuate) at the stem, crowded; yellowish white when young, becoming pink as spores mature. Stem: 3-10 cm long, 0.6-1.5 cm thick, whitish, smooth, sometimes swollen at the base; no ring or volva. Flesh: white. Odor: described differently by different sources (vague and unpleasant to mealy); not a reliable field mark. Spore print: pink to pinkish brown. Spores: angular, subglobose, about 7-10 x 7-9 um (First Nature) or 8-11 x 7-9.5 um (Wikipedia).
