California has experienced an alarming surge in mushroom poisonings, with four deaths and 40 hospitalizations linked to the toxic death cap mushroom (Amanita phalloides) between late November 2025 and early February 2026. The state health department described the outbreak as “unprecedented”, far exceeding the typical annual average of fewer than five cases.
The victims include a seasonal farm worker couple from Oaxaca, Mexico, and range in age from 19 months to 67 years. Several have required liver transplants. The epicentre of the first 35 incidents was Salinas, a central coast town with a large population from central Mexico, where mushroom foraging is common. Experts believe the death cap was mistaken for edible Amanita species familiar in their home country.
Death caps can grow up to 6 inches across and tall, with a greenish-gray cap and white gills, closely resembling edible species like puffballs. Eating half a cap or less can be lethal, with mortality rates reaching 50%. The mushrooms are also deadly to dogs. The western destroying angel mushroom (Amanita ocreata) is another highly toxic species common in coastal regions through April.
Rudy Diaz, resident mycologist of the Los Angeles Mycological Society, noted that while experienced foragers are not panicking, the public is on edge. He stressed that finding mushrooms in southern California requires skill, so foragers tend to be trained. Jess Starwood, an herbalist and forager, warned that novice foragers can easily misidentify death caps, especially as they become more common due to climate change.
The state health department has released a flyer with QR codes sharing the poisonous mushroom advisory in nine languages, including Spanish, Mandarin, Mixteco, Russian and Ukrainian. Experts advise inexperienced mushroom hunters to join local mycological societies or foraging groups to learn from experienced locals before consuming wild mushrooms.
