After Mushroom Poisonings, California Says ‘Don't Forage.’ Here’s What to Know About Death Caps

The California Department of Public Health is urging people to avoid foraging for and eating wild mushrooms this season after 21 people have been hospitalized with severe liver damage from a toxic mushroom known as the “death cap” — and one person has died.

CDPH issued the blanket advisory after detecting what the agency called two “significant clusters” of poisoning cases in Monterey and San Francisco counties, caused by the amatoxin found in the fungi.

“Death cap mushrooms contain potentially deadly toxins that can lead to liver failure,” CDPH director and state public health officer Dr. Erica Pan said. “Because the death cap can easily be mistaken for edible safe mushrooms, we advise the public not to forage for wild mushrooms at all during this high-risk season.”

The death cap mushroom, whose Latin name is Amanita phalloides, is particularly dangerous because it can easily be confused with different, safe-to-eat mushrooms because of their similar appearance and normal taste, said Bruch Reed, chief operating officer at the North American Mycological Association. The state has warned that cooking, boiling, drying, or freezing these mushrooms will not make them safe to eat, either.

“When in doubt, throw it out,” warned Reed, whose organization also has a toxicology committee. As a rule, he urged foragers at any time to never consume a mushroom they aren’t 100% sure is safe — meaning, if you’re reading this article to try to decide if you should eat a mushroom that might be a death cap, don’t.

“If you can’t distinguish between the two, if you have any doubt whatsoever, it’s not worth dying over,” Reed said.

If you’re worried about friends and family who forage and who may not know about the state’s recent warning, read on for more information about the toxic mushroom, how to spot symptoms of death cap poisoning and what to do if you accidentally eat a dangerous mushroom.

And if you experience any symptoms yourself after eating wild or foraged mushrooms, go to a hospital immediately and call California Poison Control System’s free 24-hour line at 1-800-222-1222. They can direct you to the nearest hospital and will not share your name.

Jump straight to:

• What does a death cap look like?
• What are the symptoms of death cap poisoning?
• What types of mushrooms are death caps confused with?

What are death cap mushrooms?

Just like many other mushrooms you might find on the forest floor, or even on the shelves of the supermarket, death cap mushrooms are generally white, light yellow-green or even bronze.

The death cap has a cap and stalk, and “honestly, it looks like lots of other mushrooms,” said Britt Bunyard, a mycologist, former university professor and editor-in-chief of FUNGI Magazine. He is also the author of “Amanitas of North America,” a book focused on the species that includes the death cap.

Cooking the mushroom does not eliminate its toxicity, reiterated Heather Hallen-Adams, associate professor of Practice in Food Science at the University of Nebraska, Lincoln, and the toxicology chair for the North American Mycological Association.

Hallen-Adams received a report of the poisoning last week from a hospital in Salinas, where staff were seeking identification of the mushrooms after treating patients with gastrointestinal symptoms who said they had eaten them.

Why are death caps so dangerous?

The death cap species causes 90-95% of mushroom-related fatalities worldwide, Bunyand said. The death cap mushroom itself has a mortality rate of around 50%.

“It looks like lots of other mushrooms, so there’s nothing really to tell you that it’s dangerous,” Bunyard stressed.

That goes for its taste, too, Bunyard said. While it’s technically not harmful to put the mushroom in your mouth to chew it and spit it out — which he absolutely still doesn’t recommend — this won’t be helpful either, Bunyard said, because “it doesn’t taste foul or bitter.”

“There’s no hint that it’s poisonous in any way,” he said. “There’s no foul smell about them.” And despite their lethal danger, death cap mushrooms “actually smell quite nice and they taste quite nice,” Bunyard said.

Are death caps dangerous to pets?

Yes, these mushrooms are also dangerous to pets like dogs, Bunyard said.

That said, not all animals are harmed by death cap mushrooms — and he said it’s still not entirely clear what the purpose of the toxin itself serves.

“It’s one of those things that just so happens to be incredibly poisonous to mammals and especially humans, but not a lot of other organisms,” Bunyard said.

How common are deathcap mushrooms?

With more rain comes an uptick in mushrooms like these, the experts said.

Amanita phalloides is an invasive species from Europe arriving in California around the 1930s, which has since spread rapidly up and down both the East and West Coasts, mostly near urban areas, but not yet deep or widespread in forests, Bunyard said.

“They’re just inherently around places where people are,” Bunyard said — making their proximity to humans even more dangerous.

The death cap also has a mutually dependent relationship with local trees, including the Coast Live Oak and pine trees, which are abundant across the Bay Area and state.

“Basically, it just seems that this Amanita phalloides is having a moment of fruiting in California right now,” Reed said. “No one would eat it on purpose.”

What are the symptoms of deadly mushroom poisoning?

If you’ve eaten a toxic mushroom like the death cap, you may not feel symptoms immediately, Reed said. It might take six, eight or even 24 hours to start feeling sick, with flu-like symptoms that include:

• Vomiting
• Aches
• Stomach pain
• Watery diarrhea
• Nausea
• Dehydration

In these recently reported poisonings, Hallen-Adams said symptoms didn’t show up until around 24 hours later.

You might even start to feel better, Reed said, thinking you just had the flu and not bothering to go to the hospital.

“And then two or three days later, your organs shut down, and you probably don’t make it,” Reed said. “It’s insidiously misleading.”

The state’s advisory also warned of the “deceptive” brief improvement that victims of mushroom poisoning can experience. But once the poison gets in your system, Bunyard said, it targets your liver and other organs, recirculating through your bloodstream and essentially re-dosing you with the toxin.

While you’re starting to feel better, the damage has already been done, Bunyard said. Your liver is destroyed, and you may die from the other toxins already in your body that your liver can no longer treat.

“You’re basically either on dialysis the rest of your life, or you get a liver transplant or you die,” he said. “So not only is it potentially lethal, but it’s not a good way to go.”

If you’re able to identify the toxin early and get to a hospital right away, Bunyard said, death cap poisoning is treatable — “but you wouldn’t want to chance it,” he said.

If you experience any symptoms yourself after eating wild or foraged mushrooms, go to a hospital immediately and call the California Poison Control System’s free 24-hour line at 1-800-222-1222. They can direct you to the nearest hospital and will not share your name.

What types of mushrooms are death caps easily confused with?

In California, death caps look a lot like common edible field and button mushrooms like Agaricus campestris, Bunyard said. They can also be confused with Amanita vernicoccora.

“If you don’t know anything about mushrooms, it looks real similar,” Bunyard said.

Don’t ever use AI to help you identify mushrooms, warned Reed — and never eat wild foraged mushrooms from people you don’t 100% trust to identify them.

What are some common myths about mushroom foraging?

When giving lectures, Bunyard said, people always want to know the hard-and-fast rules of what not to eat. But the No. 1 truth about mushroom foraging, he said, is that there are no real rules of thumb — except one.

“The only rule of thumb is that you really have to know exactly what the mushroom is that you’re eating before eating it,” he said. “Otherwise, you could get in trouble.”

He warned against following adages like cooking the fungi with silver and waiting for it to turn black as evidence of toxins, pure myth, he said.

And Bunyard reiterated that not every toxic mushroom gives you a warning that it’s harmful, either visually, by taste or by smell. Plus, the death cap in particular is completely safe to handle, smell and look at — and it’s not hurting anyone growing on a lawn or in a forest.

Overall, Reed said increasing mushroom knowledge via education — particularly local, in-person knowledge — can help prevent such “terrible” mistakes.

This story has been updated to clarify that the Agaricus californicus mushroom , while not deadly, is still toxic.