The poster child for psychedelic mushrooms is named after a country that doesn’t use it

Psilocybe cubensis, which produces mushrooms with whitish stalks, tawny brown caps, and subtle blue bruising, is arguably the best-known and most widely used psychedelic mushroom in the world. When Dennis and Terrence McKenna published the first reliable instructions in English for growing psilocybin mushrooms in 1976 — in the form of a book, Psilocybin: Magic Mushroom Grower’s Guide, which would go on to become a counterculture classic — their instructions were tailored to growing P. cubensis specifically. Many of the best-known strains trip-seekers look for today, including Golden Teacher and B+, are cultivated from P. cubensis. The species is, according to mycologist and psilocybe researcher at Clark University Alexander Bradshaw, “the poster child of magic mushrooms.”

But when P. cubensis, or cubensis for short, first entered the canon of Western science with an official name and description, the person who found it would never have imagined that the little brown mushroom he scooped up would one day be a global sensation.

The mushroom was collected and first given a scientific Latin name in Cuba in 1906, the same year the U.S. government began occupying the island following a contested presidential election. The man who found and named it was U.S. citizen Franklin Sumner Earle, who had moved to the island nation two years prior to direct Cuba’s Agronomical Station. Earle’s interest in fungi was the “distinctive feature of his early life,” according to his colleague Carlos E. Chardón, a trailblazing Puerto Rican mycologist. But at the turn of the 20th century, fungi were poorly understood and often studied only when they showed up as a risk to human health or crop yields, so Earle did what any fungi-lover trying to make a living would do: he levied his mycological interest into a job as a plant pathologist. His career included stints working in that capacity for the U.S. Department of Agriculture, as well as serving as a biology professor at the Alabama Polytechnic Institute, and overseeing the mycological collections at the New York Botanical Garden (NYBG).

It was while at NYBG that he received the offer to begin directing the Agronomical Station in Cuba, and though he left his post in New York to begin a new life in Santiago de las Vegas, he maintained a relationship with his old colleagues. Once on the ground in his new home, he continued to send interesting letters and specimens back to the Garden in New York, where his findings were added to the ever-growing herbarium. Among them was a collection of two tawny brown mushrooms that Earle dubbed “Stropharia cubensis.” The genus Stropharia would later be swapped for Psilocybe by the mycologist Rolf Singer, but Earle’s moniker “cubensis” — named for the fact that the specimen was found in Cuba — has stuck ever since.

I found myself wondering if Earle had any idea that this mushroom was special; so special, in fact, that it’s the reason we’re still talking about him a century later. So one sunny day in April, I hopped on the train from Brooklyn and headed toward the Bronx, where Earle’s letters were filed away in the library archives at the New York Botanic Garden.

Thumbing through his hundred-year-old correspondences with colleagues, I came across staffing and interpersonal queries, and evidence of Earle’s salary (in 1904, before he took the position in Cuba, he had been making $1800 a year at the Botanic Garden, equivalent to about $67,352 in 2026 dollars; he wrote later that year asking for a raise to $2500, or the equivalent of about $93,545 today, before accepting the job in Cuba). Once in Cuba, the letters document a shift in his relationship with Cuban authorities — from “my relations with the government continue to be eminently satisfactory” in 1904, shortly after he arrived, to a proclamation that he’d lost a “long drawn out fight” with the Cuban Secretary of Agriculture by 1906. Later that year, he would resign from his post, though he stayed in Cuba and continued to work on agricultural issues.

But nowhere in his letters are there any mentions of cubensis, or any hint that Earle knew what powers it might possess.

Was it possible that these mushrooms were culturally significant, and Earle had missed that significance entirely? He was, after all, a U.S. scientist focused on pathogenic threats to sugar cane. Or was it that Cubans at the turn of the century weren’t seeking altered states of consciousness via these mushrooms? Were they even doing so now? I reached out to some Cuban mycologists to find out.

This is the opening to my latest story for The Microdose, a journalism project of the UC Berkeley Center for the Science of Psychedelics. To learn what the Cuban mycologists told me, and for surprising theories as to how P. cubensis spread, read the full story here.