When Donna Davis looked in the mirror, she saw that her skin had turned yellow.

As KQED tells her story from 2014, Davis, fell ill after enjoying a "delicious" soup she cooked from mushrooms foraged at Salt Point State park in Sonoma.

But Davis had made an error, mistaking poisonous Amanita phalloides — commonly known as "death caps" — for edible hedgehog mushrooms. Unlike hedgehogs, death caps are often olive-green in color and have gills, or little ribs under their heads. Nearly a day after eating her soup, Davis was dehydrated, confused, and frightened.

After being treated in a hospital and narrowly avoiding a liver transplant, Davis was one of the lucky ones. Between 2010 and 2015, 57 became sickened and five died after eating death caps. One mushroom is enough to kill a person, and dogs, says Debbie Viess of the Bay Area Mycological Society, "die in droves."

As recent rains have brought a boom in mushroom growth, so too have they invited death caps. The "strikingly beautiful mushroom" according to the Bay Area Mycological Society, "can be found everywhere," in California as Dr. Craig Smollin, Co-Director of the San Francisco division of the California Poison Control System, told KCBS. "They could potentially grow in someone’s backyard.”

So what's an amateur forager to do? "Assume nothing, and learn for several seasons before you eat any wild mushrooms," says Viess. "Use good, regional books, find a mentor, and have your initial IDs checked by more knowledgeable and trusted identifiers." Of course, you can also see Viess' post on the "invasion of the death cap." Or you can just forego foraging altogether.

Related: Generous Rain, Regulations Make Point Reyes A Mushroom Magnet