" Rye growers face another challenge: the grain is vulnerable to a fungus called ergot (Claviceps purpurea). The spores attack open flowers, pretending to be a grain of pollen, which gives them access to the ovary. Once inside, the fungus takes the place of the embryonic grain along the stalk, sometimes looking so much like grain that it is difficult to spot an infected plant. Until the late nineteenth century, botanists thought the odd dark growths were part of the normal appearance of rye. Although the fungus does not kill the plant, it is toxic to people: it contains a precursor to LSD that survives the process of being brewed into beer or baked into bread. While a psychoactive beer might sound appealing, the reality was quite horrible. Ergot poisoning causes miscarriage, seizures, and psychosis, and it can be deadly. In the Middle Ages, outbreaks called St. Anthony’s fire or dancing mania made entire villages go crazy at once. Because rye was a peasant grain, outbreaks of the illness were more common among the lower class, fueling revolutions and peasant uprisings. Some historians have speculated that the Salem witch trials came about because girls poisoned by ergot had seizures that led townspeople to conclude that they’d been bewitched. Fortunately, it’s easy to treat rye for ergot infestation: a rinse in a salt solution kills the fungus. "
― Amy Stewart , The Drunken Botanist: The Plants That Create the World's Great Drinks