I love a good mushroom Facebook group. I really do. Scroll for ten minutes and you’ll see lovely finds, great photos and people getting properly excited about a fungus. But I also can’t scroll for ten minutes without wincing. Someone posts a blurry photo of a brown mushroom taken from above, in a hand, in poor light. Within minutes: “Looks good to eat!” “Yep, had those last week, delicious.” A thumbs up. A heart. And somewhere, someone is firing up the frying pan. A photo is not a mushroom Mushroom ID is a hands-on, nose-on, look-underneath job. To name a mushroom with any confidence you need to know what’s going on under the cap (gills, pores, spines?), what the stem base looks like (is there a little sac buried in the soil?), what it smells like, what it’s growing on or near, how the flesh changes when you cut it, and sometimes what colour the spores are. A single photo from above gives you almost none of that. The dangerous mushrooms in the UK are masters of looking like the harmless ones. A death cap can pass for something you’d happily put on toast. The mistake doesn’t show up as a stomach ache that evening. It can feel fine for a day or so before the damage to your liver really kicks in. Why the advice is so often bad It’s mostly not malice, it’s just how Facebook works. Confidence is rewarded. The person who says “definitely edible!” gets the likes. The person who says “I can’t tell from that photo” gets ignored. Pile-on identification. Once three people say it’s one thing, the fourth agrees, and suddenly it’s settled. It isn’t. It’s just three people guessing the same way. “I’ve eaten them for years.” Great, so has everyone who’s ever been lucky. That’s not evidence, it’s survivorship. Old wives’ tales. “If slugs eat it, it’s safe.” “Peel the cap and it’s fine.” “A silver spoon will turn black.” All nonsense, and all still circulating. Nobody is accountable. If the advice goes wrong, the commenter has moved on and you’re the one in A&E. There are real experts on there I don’t want to throw the baby out with the bathwater. Some groups are brilliant, and some of the people in them know their stuff, often experienced mycologists and long-time foragers who give their time for free. You can usually spot them. They ask for more photos: top, underside, stem base, cut through the middle. They say “I can’t tell from this” without any embarrassment. They tell you why they think something is what it is, not just that it is. And they’ll often say “don’t eat it, please get someone to look at it in person,” which is a good sign, not a cop-out. If a group is full of confident one-word answers and emojis, treat it as entertainment, not education. So what should you do? Never eat anything on the strength of an online ID. Ever. Not from Facebook, not from an app, not from me. Learn in person. Go on a guided foray or a workshop, or join a local fungus group. Having someone physically show you the gills and the stem base is worth a hundred photo threads. Use more than one good field guide, and learn the features, not just the pictures. Start small. Pick a handful of distinctive species, get to know them really well, and build from there. When in doubt, throw it out. A missed meal is a very cheap price to pay. And if you or someone you know has eaten something and feels unwell, don’t wait to see how it goes. Get to A&E or call NHS 111, and take a sample of the mushroom with you if you can. Mushrooms are one of the great joys of this time of year. Let’s keep it that way. If you’d like to learn properly, have a look at our foraging workshops, and come and meet some mushrooms in person.

Please Don’t Eat a Mushroom Because Someone on Facebook Said It’s Fine