California mushroom poisoning is on the rise. Here’s what to do to prevent exposure

David Yturralde arrived at a mushroom talk in Newport Beach recently armed with a pen and paper and a bunch of questions. The goal, he said, was to kill the bacteria that appeared in his lawn after a heavy winter rain.

He has long loved the mushrooms growing on the front lawn of his San Clemente home, but has always been afraid to pick any. And there is no way he collected the taste, he said.

“Mushrooms are mysterious little things because right from the start your parents tell you that you should not eat them when you are a child,” he said.

But after hearing about recent illnesses and deaths related to the death cap mushroom, Amanita phalloides, California, Yturralde and several others gathered in a conference room of the Environmental Nature Center wanted answers about which mushrooms in the area are deadly.

In the past three months, California has seen a sudden increase in the number of people who have become ill and died after accidentally eating poisonous mushrooms found in the wild. While the die-off occurred along the central and northern coast of California, the situation has caused concern and discussion among the mycological and forager communities throughout the Golden State.

The latest death was reported on Jan. 27 Contra Costa County public health officials confirmed that a 60-year-old man died after eating wild mushrooms, bringing the number of people who have died from the fungus to four.

Public health officials have not been able to identify which wild mushrooms killed the man, said Nicola Gillette, spokeswoman for Contra Costa Health. But officials said the man, described as “of Spanish descent,” died after eating wild mushrooms foraged in a state park.

“Initial information indicates that this man may have made a mistake with edible mushrooms in his country,” said Gillette.

The California Department of Public Health reported 39 disease-related deaths, including four deaths and three liver transplants, between Nov. 18 and Jan. 18.

In a typical year, the California Poison Control Center can detect five cases of illness related to poisonous mushrooms, according to authorities.

The last major outbreak occurred in 2016 with 14 reported cases, and while there were no deaths, three people required liver transplants and one child suffered “permanent neurologic disability.”

In most of these cases, the California Department of Public Health reported that 60% of the affected people speak Spanish as their primary language – some affected people speak Mixteco, Mandarin Chinese, Ukrainian, Russian and English.

The incidents in the Latino community this year can be puzzling, said Mike McCurdy, president of the San Francisco Mycological Society.

The community has been working closely with the country’s public health department to create warning signs and leaflets with a QR code leading to more information in multiple languages ​​that can be distributed in recreational areas such as parks, nature reserves and hiking trails.

Often, people are accidentally poisoned after accidentally eating a wild mushroom they thought was safe, McCurdy said.

Some cases are worse. In 2025, Erin Patterson, a 51-year-old Australian woman, was sentenced to life in prison for murdering three relatives and attempting to kill another by deliberately feeding herself beef Wellington that included poisonous fungus in the ingredients.

Two of the most poisonous mushrooms that can be found in the state are the death cap and the western destroying angel mushroom, Amanita Ocreata. Death cap mushrooms have a dome-shaped cap that may have olive or yellow tones, while western destroying angel has a cream or ocher colored cap.

At the beginning of Joanne Schwartz’s presentation in Newport Beach recently, the novice mycologist acknowledged the number of recent deaths caused by toxic mold.

“Guess what, these mushrooms are right here in Orange County,” Schwartz said. “You might have one on your lawn.”

He warned about 20 people who were present that some edible mushrooms look like they are poisonous, many of them grow together and if a person collects a type of mushroom in another part of the world, there may be a deadly appearance in another place.

While mushroom poisoning is concentrated in the north, reports of death and disease have trickled down to Southern California, sparking panic among those who monitor these wonders, said Rudy Diaz, president of the Los Angeles Mycological Society.

When mushroom poisoning hits the headlines, people who aren’t part of the mushroom community often see those who don’t care or destroy habitats, he said.

On a recent trip with a friend, Diaz said he was looking for mushrooms he found along the way and a stranger “scolded me for doing such a dangerous thing.”

“For people who have been able to develop that kind of spiritual connection with the world through their years of observation and learning, eating the things you eat is like an active communion with these places you love and know,” said Diaz.

But experts, including Diaz, say eating mushrooms is not a necessary part of viewing, studying and appreciating them.

For those who are familiar with the mushrooms of Southern California, there is no sense of panic about the possibility of poisoning because poisonous mushrooms are not very common in the southern part of the state.

In Northern California, deadlocks are common in local parks, “whereas here in Southern California you have to dig through oak litter before you can see things,” Diaz said.

However, the message from the mycology community and mycologists throughout the region is one of caution: Unless you are familiar with your area, have an expert to consult with or are part of a mushroom or feed group, you should not eat wild mushrooms.

Mycologists use dichotomous keys to identify mushroom species based on their physical characteristics including cap, stem, ring and gills.

A mistake people outside the mushroom community or beginners make when identifying mushrooms is relying solely on social media, a local guide or an app like iNaturalist, says Bob Cummings, a leading mycologist in Santa Barbara. Just comparing the mushrooms to a photo is not enough to make an accurate species identification, he said.

Schwartz encouraged the public to take an active role in public science. He said his hope is that people get involved with mushrooms because there is a lot to learn about the more than 1,500 species in Orange County and the more than 3,000 species of fungi in the state.

Mushrooms, poisonous or not, are good for everyone to pick and observe, he said.

Yturralde came out of the weekend interview thoughtful.

“I’m open to learning more about mushrooms, but I don’t like to eat anything I find,” Yturralde said. In other words, I learned that it is better to eat only what is inside [grocery store].”