There’s a saying in the mushroom-picking community that all mushrooms are edible but some mushrooms are only edible once.
That’s why, when news spread on Twitter of an app that used “revolutionary AI” to identify mushrooms with a single picture, mycologists and fungi-foragers were worried. They called it “potentially deadly,” and said that if people used it to try and identify edible mushrooms, they could end up very sick, or even dead.
Part of the problem, explains Colin Davidson, a mushroom forager with a PhD in microbiology, is that you can’t identify a mushroom just by looking at it. “The most common mushroom near me is something called the yellow stainer,” he told The Verge, “and it looks just like an edible horse mushroom from above and the side.” But if you eat a yellow stainer there’s a chance you’ll be violently ill or even hospitalized. “You need to pick it up and scratch it or smell it to actually tell what it is,” explains Davidson. “It will bruise bright yellow or it will smell carbolic.”
And this is only one example. There are plenty of edible mushrooms with toxic lookalikes, and when identifying them you need to study multiple angles to find features like gills and rings, while considering things like whether recent rainfall might have discolored the cap or not. Davidson adds that there are plenty of mushrooms that live up to their names, like the destroying angel or the death’s cap.
“One eighth of a death cap can kill you,” he says. “But the worst part is, you’ll feel sick for a while, then you might feel better and get on with your day, but then your organs will start failing. It’s really horrible.”
The app in question was developed by Silicon Valley designer Nicholas Sheriff, who says it was only ever intended to be used as a rough guide to mushrooms. When The Verge reached out to Sheriff to ask him about the app’s safety and how it works,…