Psilocybin Mushrooms · Psilocybe semilanceata
Liberty Cap
Psilocybe semilanceata — the Liberty Cap — is arguably the most ecologically widespread psilocybin mushroom species in the world, found across the grass-covered hillsides of the British Isles, northern Europe, Scandinavia, and the Pacific Northwest. It has been documented in over 17 countries across Europe and North America.
Semilanceata translates from Latin as 'half-spear-shaped', describing its distinctive conical to bell-shaped cap with a sharp papilla. It was one of the first wild psilocybin mushrooms to have its psychoactive content analytically confirmed — Albert Hofmann (who first synthesized psilocybin from Psilocybe mexicana in 1958) confirmed psilocybin and psilocin content in P. semilanceata specimens in 1963.
Potency of P. semilanceata is meaningfully higher than typical P. cubensis, with analytical studies reporting 0.2–2.37% psilocybin content by dry weight. The wide variance reflects both collection conditions (temperature, moisture) and individual specimen age. This places P. semilanceata as a genuinely more potent species on a per-gram basis than most cultivated P. cubensis strains.
Active Compounds
Psilocybin (up to 2.37% by dry weight reported), Psilocin, Baeocystin
P. semilanceata grows in old, unfertilized grasslands where it associates with grass root systems — it is not actually dung-loving like P. cubensis, though it may occur near areas grazed by sheep or cattle. It prefers acidic, moist soils and cool temperatures, fruiting primarily in autumn.
The fruiting body is small: cap 0.5–2.5cm diameter, sharply conical to campanulate, pale tan to dark brown when wet, drying to cream-yellow. A distinctive translucent gelatinous skin (pellicle) coats the cap — this can be peeled off and is characteristic of the species. Stem is thin, wiry, wavy, and bruises blue readily.
Identification confidence is critical — several grass-associated mushrooms can be confused with semilanceata, some of which are toxic (e.g., Galerina marginata contains amatoxins). A reliable identification requires the gelatinous pellicle, sharp papilla, blue bruising, and dark purple-brown spore print in combination.
- Scientific Name
- Psilocybe semilanceata
- Potency
- Moderate–High
- Origin
- British Isles, Northern Europe, Pacific Northwest (North America)