Chlorophyllum molybdites

Cap

(5)10-30(40) cm in diam., paraboloid to conical-obtuse then hemispherical, broadly convex to convex-spreading, slightly oblong at disc to depressed when ripe, dry, glabrous to slightly tomentose-felted and brown or sometimes tinted vinous at first, with crispy cuticle with expansion to form coarse brown scales, arranged concentrically towards the center, smaller and scattered towards the edges, on a whitish ground, yellowish-white to buff-brown, with a curved margin at first, then spreading to raised, sometimes wavy, appendiculated with velar flaps at the beginning

Gills

free, broad, up to 1.5 cm wide, with lamellae, closely packed, sometimes long white to cream at first, then dark gray to buff brown, greenish olive with age, with often brown edges

Stem

5-25 x 0.8-2.5 cm, subequal, sometimes slightly broadened towards base to subbulbous, firm, stuffed, smooth, indistinctly fibrous or with scattered scales at first, whitish, fading slightly to brownish or dark gray , becoming dull wine-brown when crushed, then distinctly grey-brown with age

Partial veil

membranous, thick, felted, white, leaving a superior ring on the foot, ample, pendent, persistent, often sliding, with torn double edge, buff to tan

Flesh

thick, firm at first, soft with age, white, unchanging or sporadically becoming reddish-brown to pale reddish-pink, almost orange in the base of the foot when cut or crushed

Smell and flavor

indistinct or unpleasant odor and indistinct, sweet flavor

Spore

greenish

Spores

ovoid to ellipsoid and sometimes truncate at the apex seen from the front, strongly unequal seen from the side, smooth, moderately thickened wall, with prominent hilar appendage and small germ pore, dextrinoids, (8)9-11.5(13) x 6.5-9µm

Cheilocystidia

abundant, often clavate to fusiform-bellied, up to 50 x 25 µm

Pleurocystidia

absent

Pileipellis

in cutis
formed of tangled, narrow elements

Mode of growth

scattered, gregarious, or often in large circles

Ecology

saprotrophic
especially on soil in open grassy areas, lawns, pastures, sometimes parks and gardens

Period

July to September

Frequency

common in the southern and western United States, rare in Quebec and brought from greenhouses, among tropical plants, not in nature

Edibility

toxic
agent of gastrointestinal disorders
easily confused with Chlorophyllum rhacodes

Remarks

This species is characterized by its imposing size, with a cap up to 40 cm in diameter. and stem up to 25 cm in length, its hemispherical cap and flattened in the center, whitish, with coarse brownish scales, its free blades, whitish then greenish, its ample, double, sliding ring, its greenish spores and its growth in grassy environments open.
This magnificent and impressive mushroom often grows in large witch rings. It is probably the most common cause of mushroom poisoning in the United States. It is one of the most common urban lawn fungi in southern North America.
It was reportedly found in southern Ontario. Young specimens, in the button stage and when in drumstick form, are almost indistinguishable from the excellent edible C. rhacodes, which often causes confusion in poisoning. The latter is distinguished by its whitish spore.