San Pedro cactus aka "Huachuma" is native to the Andes of Colombia, Bolivia, Peru, and Ecuador. Containing mescaline and other psychoactive alkaloids, it has been used ceremonaly by South American shamans for more than 3,000 years. In the former Incan capital city of Cuenca, an Ecuadorian bank is guarded by a healthy garden of the fast-growing navtive succulent.