Revised February 6, 2006; October 1, 2007; April 5, 2013; September 21, 2016; and March 29, 2017.
Copyright 1998-2017 by John W. Allen.

Psilocybe baeocystis


Psilocybe baeocystis Singer and Smith

Cap: 1.5 cm to 5.5 cm broad to olive. center convex to conic. translucent when moist, appears pleated towards bottom portion of cap. Often staining blue to blue-green when damaged.

Gills: Attached. Dark purple.

Stem: 50-70 x 2-3 mm long. White cream to yellow top. Covered with white filaments.

Spores: 10-13.2 x 6.2-7.

Sporeprint: Purple gray.

Habitat: Psilocybe baeocystis was 1st discovered in Eugene, Oregon in 1945. Once considered rare, this species was a very common mushroom appearing in mulched garden beds under rhododendrons and rose bushes during the late 1970s and early 1980s, sometimes growing in amongst groupings of Psilocybe stuntzii in lawns and with Psilocybe cyanescens in alder mulched garden beds. Although this species grows abundantly some in lawns or grassy areas rich in humus or lignin and/or in alder wood chips and bark mulch, it is sometimes very hard to find.

Distribution: From Eugene, Oregon to Seattle, Washington, up to British Columbia, Canada. Once considered rare, it is now common.

Season: June to October in lawns. From late September through December and sometimes into January in mulched garden beds.

Dosage: 1 to 2 large mushroom specimens or from 2 to 4 small specimens.

Comment: A very potent species when fresh. Stains intensely blue when damaged. Loses much potency when drying.

In the mid to late 1960s, two young children, both six years old reportedly died after allegedly consuming Psilocybe baeocystis. However, photographs given to the author by the physicians involved in the subsequent attempted treatment and later death of these children, one in Washington and a second reported death in California, were identified by (JWA) as Psilocybe cyanescens. In both incidents, entire families had also consumed these mushrooms and did not die. Because of this misidentification by the late Chicago mycologist Rolf Singer and Alexander H. Smith who noted the species in their 1958 monograph on the genus Psilocybe, numerous mushroom field guides for both edible and psilocybian mushrooms described it as a very dangerous and toxic mushroom which could cause death. Over the years, few authors have corrected this error in reporting the correct identification of the species as Psilocybe cyanescens.

Bluing in Psilocybe baeocystis
Lawn Varieties of Psilocybe baeocystis
Woodchip Varieties of Psilocybe baeocystis
Return to Species Index
Return to Main Index