Wild psilocybin mushrooms in Washington, and their deadly lookalikes

Seattle's own species

Daniel Stuntz taught at the University of Washington from 1940, was its leading mushroom expert for decades, and was the founding scientific adviser of the Puget Sound Mycological Society. In 1976 the mycologists Gastón Guzmán and Jonathan Ott described a new species in the journal Mycologia, noting that it "was first collected on the campus of the University of Washington in Seattle," and named it Psilocybe stuntzii in his honor; the reference collection is credited to Stuntz in autumn 1973 (Guzmán and Ott, 1976). It's sometimes called the "blue ringer."

P. stuntzii grows on lawns, in fields and on bark mulch in western Washington and around Vancouver, B.C., from about August to December. It also shows the problem that still defines foraging here: field guides warn that it's easily confused with Galerina, a small brown mushroom that can kill.

The region's other psilocybin species

Wavy caps, Psilocybe cyanescens

The species most associated with the Puget Sound region. It's named for its wavy cap edge, bruises blue-green where handled, and leaves a dark purple-brown spore print. It fruits in fall on wood chips and woody debris, very often in urban landscaping, from southern British Columbia to southern California (UBC Beaty Museum). It was described in 1946.

Liberty caps, Psilocybe semilanceata

A small mushroom with a pointed, nipple-like cap tip, found in unfertilized grassland and pasture rather than on dung, from fall into winter. It's one of the most widespread psilocybin species in the world.

Psilocybe azurescens

Described by Paul Stamets and Jochen Gartz in 1995 from a collection at Hammond, Oregon, near Astoria. It grows on wood chips and in sandy soil near dune grass along a narrow coastal strip reported to run from Oregon's central coast north to Washington's Grays Harbor, from late September into January. Stamets, who studied at Evergreen State College in Olympia, built his mushroom company, Fungi Perfecti, in the South Sound.

The problem: Galerina marginata

Galerina marginata is a small brown mushroom that grows on rotting wood and in urban wood chips and is common across the Pacific Northwest. It contains amatoxins, the same toxins that make the death cap deadly, and cooking or drying doesn't destroy them. One study found amatoxins in all 27 specimens it tested (Enjalbert et al., 2004).

Mycologists separate it from wavy caps by several features together, including a rusty-brown spore print rather than a purple-brown one and a stem that darkens toward black rather than bruising blue (UBC Beaty Museum). The catch is that both species vary, old or rain-soaked specimens lose their features, and both can grow in the same patch of chips, so a bag of "wavy caps" can contain a Galerina. Blue bruising on some mushrooms in a collection says nothing about the others. That's why experienced mycologists won't vouch for a mushroom from a photo.

How amatoxin poisoning unfolds

1. Nothing, for 6 to 24 hours. The delay is what makes it so dangerous: by the time anyone feels sick, the toxin is already absorbed.
2. Severe vomiting and diarrhea, often for a day or more.
3. A false recovery, when the person seems to improve.
4. Liver and kidney failure several days in, which can require a transplant or be fatal.

Early treatment improves the odds, which is why the Washington Poison Center wants a call as soon as someone may have eaten a mushroom that wasn't positively identified.

Death caps are here too

The death cap, Amanita phalloides, has spread up the West Coast. The University of Washington warned in October 2019 that death caps had been found on its Seattle campus (KIRO 7). In California, a surge of death cap poisonings in the 2025–26 season had put 35 people in the hospital and killed three by early January 2026 (California Medical Association). Death caps aren't psilocybin lookalikes, but they're a reminder that the deadliest mushrooms in the region grow in parks and yards, not deep woods.

Wild species versus what's sold

Almost all psilocybin mushrooms people buy, including in Oregon's licensed program, whose rules limit products to a single species, are cultivated Psilocybe cubensis. It's a tropical and subtropical species that doesn't grow wild in the Northwest. Its named strains, like Golden Teacher (written up by our sister shop), are all the same species grown indoors. That's one reason the cubensis supply has largely replaced foraging: it removes the lookalike problem, though not the legal one.

The law on picking

Psilocybin mushrooms are a controlled substance in Washington whether they're grown or wild, so picking them is possession under RCW 69.50.4013, a gross misdemeanor. Seattle's 2021 resolution makes personal possession a lowest police priority inside the city; it doesn't change the law. Parks and private land have their own rules on removing anything at all.

Learning to identify mushrooms safely

If wild mushrooms interest you, the safest way in is the Puget Sound Mycological Society, which Stuntz helped found. Its Wild Mushroom Show fills Shoreline Community College with hundreds of identified species each October, and its fall identification clinics, classes and field trips teach the skills properly, starting with edible species and their poisonous lookalikes.

Last checked against the sources above on Oct 20, 2026. Spotted something out of date? Tell us.