Known by numerous names—Liberty Caps, Blue Legs, Pixie Caps, Witches Hats—Psilocybe semilanceata is an unassuming innocent-looking mushroom, often happily growing next to many similar species, including Panaeolus spp. and Protostropharia semiglobata. Like Psilocybe cubensis, Liberty Caps grow in fields and pastures, but prefer the cold of temperate climates. Found growing in fall and spring, these delicate-looking, slender mushrooms are among the most potent Psilocybe species.