OAKLAND, Calif. (KGO) -- The recent rain isn't just restoring green grass to our hillsides. It also means toxic mushrooms are again growing in Bay Area open spaces.
"With the first rains really dangerous mushrooms do start coming out," said Dave Mason, East Bay Regional Park District Public Information Supervisor.
Fungus may be fabulous to nature lovers, but with the new winter crop comes a warning.
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"Well they're deadly is what the public should know when it comes down to it," said Mason.
Names like Death Cap and Western Destroying Angel foreshadow what some mushrooms can do.
According to the East Bay Regional Park District:
The Death Cap and Western Destroying Angel mushrooms contain amatoxins, a group of molecules that inhibit cellular metabolism in many animals. In mammals, the liver and kidneys are typically the first organs affected after ingestion. Symptoms don't usually appear until up to 12 hours after consumption, beginning as severe gastrointestinal distress and progressing to the liver and renal failure if treatment is not sought immediately.
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Mushrooms grow along trails and at the base of trees making them easy for children and dogs to get a hold of, which is why you need to be vigilant in the winter.
"I am on the lookout as soon as it starts raining," said Pete Muller, Oakland resident. He walks dogs in Oakland's Temescal Regional Recreation Area.
"Some of them eat anything. Some of them couldn't care less," said Muller about the dogs.
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People may be tempted to forage mushrooms for more than just food. They can make beautiful natural dyes or are sometimes used to make prints. Tilden Regional Park Supervising Naturalist Sara Fetterly collected mushrooms for educational purposes, but the general public cannot pick in the district's 73 parks.
"We have a rule basically no collecting of any mushrooms allowed in East Bay Regional Parks and we do advise pet owners to keep a close eye on their dogs," said Mason.
So if you feel like fungi Berkeley Bowl has 15 to 20 different varieties as do other grocery stores.
"You have to remember that most mushrooms are poisonous and there's a lot of look-alike mushrooms out there that people might think are a morel or a button and it's not," said Steve Tsujimoto, Berkeley Bowl General Manager.
More information on mushrooms is available on the Bay Area Mushrooms website.
Information from the California Poison Control Center can be found here.
Information on keeping your pets safe from poisonous mushrooms can be found here.
Bay Area rain prompts toxic mushroom warning