Wild species

Wavy Cap

Psilocybe cyanescens

aka Potent psilocybe · Psilocybe cyanescens

A wood-loving Psilocybe named for the undulating margin of its caramel-to-chestnut cap. Among the most potent psilocybin mushrooms ever tested, it has spread far beyond its native Pacific Northwest range by hitchhiking in commercial landscaping mulch.

Field marks

Wavy undulating cap margin
Caramel to chestnut cap
Strong blue bruising
Thin whitish stem
Purple-brown spore print
Fruits on wood chips

Habitat

Lignin-rich wood debris — wood chips, mulched garden beds, rotting hardwood — in the Pacific Northwest and San Francisco Bay Area, with naturalized populations in Western Europe and New Zealand. Fruits as temperatures cool, roughly October through February.

Relative potency

very highRelative only — this guide gives no dosing guidance.

Lookalikes — read this twice

Deadly Galerina marginata is the critical lookalike: it shares wood-chip habitat and a similar brown cap, never bruises blue, and prints rusty brown rather than purple-brown. A spore print is essential before trusting any identification of a wood-chip mushroom. Leratiomyces ceres shares the same beds but is bright orange-red and does not bruise. Psilocybe azurescens is a closely related species that can co-occur, typically larger with a less pronounced wavy margin.

Deadly species grow in the same places as psilocybin ones and can resemble them closely. Never eat a wild mushroom identified from a website — including this one.