Habitat: Found in fields or pastures, especially those rich in manure
Conservation Status: Not of concern
Spores are chocolate-brown; growth up to 3 inches; cap diameter up to 4 inches. Agaricus arvensis grows in pastures as well but is generally much bigger with a pendulous ring. Entoloma sinuatum has pink spores, no ring, and has a mealy smell. Amanita phalloides has white spores, has a prominent volva at base of stipe, and has a sickly sweet smell.
Sources: Trudell, Steve and Joe Ammirati. Mushrooms of the Pacific Northwest, Timber Press, Inc. 2009. Roberts, Peter and Evans, Shelley. The Book of Fungi. Chicago, The University of Chicago Press, 2011.