Taxonomy and Systematics
Species: Agaricus placomyces Peck
Agaricus placomyces caps are 2.5-9 cm wide and convex, becoming, over time, broadly convex with a low umbo. Caps are primarily white, but covered with a delicate and distinctive pattern of tiny grayish-brown scales. Flesh is white. The oder of A. placomyces is unpleasant -- like phenol, according to Mushrooms of Northeastern North America. Gills are white becoming brown with age. Stalk is smooth, white, and sometimes bulbous on the bottom. Spore print is dark brown. Veil leaves a definite, single-layered ring on stalk; often a cottony remnants of veil remains attached to mature mushrooms.
Agaricus placomyces fruits from June -- September. It can be found growing in woodlands (either scattered or in groups), in grassy areas with trees, or on sawdust piles.
According to Mushrooms of Northeastern North America, this species is often confused with Agaricus pocillator and/or Agaricus meleagris. A. pocillator can be identified by the double-layered ring left by its partial veil, and its lack of brown stains and brown liquid. A. meleagris (poisonous) lacks brown liquid and stains as well -- and has a strong smell of phenol. I strongly suspect that what I have is A. placomyces -- but I cannot be entirely sure.
Campus distribution and habitat
My Agaricus placomyces specimens (they grew in a cluster of four) were found in the deciduous woods behind Jennings at 1:30 pm on Monday, 12 September, 2011.
- Barron, George L. Mushrooms of Northeast North America: Midwest to New England. Edmonton: Lone Pine, 1999. Print.
- Bessette, Alan E., Arleen R. Bessette, and David W. Fischer. Mushrooms of Northeaster North America. Syracuse, NY: Syracuse UP, 1997. Print.
- Arora, David. "Agaricus Placomyces." Wikipedia, the Free Encyclopedia. Web. 15 Sept. 2011. <http://en.wikipedia.org/wiki/Agaricus_placomyces>.