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Agaricus silvicola

[ Basidiomycetes > Agaricales > Agaricaceae > Agaricus . . . ]

by Michael Kuo

Defining features for this widely distributed Agaricus include:

  • Woodland habitat;
  • A fairly smooth, white cap;
  • Yellow staining (rub the edge of the cap repeatedly);
  • "Placomycetoid" (tall and slender) rather than "campestroid" (short and stocky) stature;
  • A sweet (faintly anise- or almond-like) odor;
  • A yellow reaction to KOH;
  • Fairly short (5-7.5 µ) spores.

I am treating Agaricus abruptibulbus as a synonym of Agaricus silvicola, but some authors separate it on the basis of its abruptly bulbous stem.


Ecology: Saprobic; growing alone, scattered, or gregariously in woods or at the edges of woods; summer and fall (also winter in California); widely distributed in North America.

Cap: 5-18 cm; convex at first, becoming broadly convex or flat; dry; whitish, sometimes developing yellowish stains; smooth or with innate, pressed-down fibers at maturity; bruising yellow, especially along the margin.

Gills: Free from the stem; close; whitish at first, becoming pinkish to pinkish gray and eventually brown; when young covered by a whitish or yellowish-stained partial veil that usually features patches or a "cogwheel" pattern.

Stem: 5-20 cm long; up to 2.5 cm thick; equal, or with a slightly to substantially and abruptly swollen base; smooth, or with fine fibers below the ring; white, often developing yellowish stains; usually bruising yellowish; with a persistent, large ring.

Flesh: Thick and white throughout; often yellowing slightly when sliced, but not turning dramatically and instantly yellow in the base of the stem.

Odor and Taste: Odor sweet (reminiscent of anise or almonds) when young and fresh, becoming less distinctive; taste pleasant.

Chemical Reactions: Cap yellow with KOH.

Spore Print: Dark brown.

Microscopic Features: Spores 5-7.5 x 3.5-4.5 µ; elliptical; smooth.

REFERENCES: (Vittadini, 1832) Peck, 1872. (Saccardo, 1887; Kauffman, 1918 [Psalliota]; Smith, 1975; Freeman, 1979; Smith, Smith & Weber, 1979; Arora, 1986; States, 1990; Phillips, 1991/2005; Lincoff, 1992; Horn, Kay & Abel, 1993; Evenson, 1997; Barron, 1999; Roody, 2003; McNeil, 2006.) Herb. Kuo 09030502, 09230606.

"Agaricus sylvicola" is an alternate spelling.

Further Online Information:

Agaricus silvicola at MykoWeb
Agaricus sylvicola at Roger's Mushrooms
Agaricus abruptibulbus at Roger's Mushrooms
Agaricus silvicola at Fungi of Poland


Agaricus silvicola

Agaricus silvicola

Agaricus silvicola

Agaricus silvicola

Agaricus silvicola

Agaricus silvicola

Agaricus silvicola

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Cite this page as:

Kuo, M. (2007, May). Agaricus silvicola. Retrieved from the MushroomExpert.Com Web site: