How to Tell if a Mushroom Is Poisonous: 15 Myths Debunked

Ask around in any village in autumn and you’ll hear a handful of tried-and-tested rules for telling good mushrooms from bad ones: sniff it, check whether the slugs have tasted it, stir it with a silver spoon. These tips have been passed on with the best intentions, often for generations. Sadly, they don’t work. Switzerland’s official mushroom inspectors, VAPKO, explain that many of these beliefs arose because people lacked knowledge and good reference books, and that trusting them can have fatal consequences (in German).

The good news is that the real answer to “how do I tell if a mushroom is poisonous?” is simple, and it leaves plenty of room for the joy of foraging. Let’s clear away the myths first.

The short answer: there is no test

There is no smell, taste, colour, shape or household trick that tells you whether a mushroom is safe. The City of Vienna states that no general feature reveals an inedible or poisonous mushroom, and Austria’s health portal adds that there are no universal rules that apply to all mushrooms (both in German). The only reliable way is to know the exact species, and to have anything you’re unsure of checked by an expert.

Myths about smell, taste and animals

Myth 1: “Poisonous mushrooms smell bad”

False. The deadly death cap can smell sweet, according to Austria’s health portal, and the poisonous livid pinkgill is a handsome mushroom that smells of flour, according to VAPKO. Smell can be one small clue in a species description, but it can never prove a mushroom is safe.

Myth 2: “If it doesn’t taste bitter, it’s fine”

False. Poisonous mushrooms don’t have to taste bitter or sharp. Never taste a wild mushroom to test it.

Myth 3: “If slugs or animals have eaten it, it’s safe”

False. Slugs also eat death caps, as both VAPKO and the City of Vienna point out. A nibbled mushroom tells you nothing about whether it’s safe for people.

Myths about kitchen tricks

Myth 4: “Poisonous mushrooms turn a silver spoon black”

False. Death caps don’t blacken silver, and VAPKO lists the silver spoon among the old wives’ tales. The German Mycological Society (DGfM) agrees that no object, metal or plant can reveal whether a mushroom is poisonous (in German).

Myth 5: “An onion cooked with them changes colour”

False. VAPKO names the onion test as another old wives’ tale.

Myth 6: “Cooking or blanching makes them safe”

False. According to VAPKO, poisonous mushrooms stay just as poisonous however long you boil them, and that includes death caps. Cooking matters for edible mushrooms, but it never turns a poisonous one into food.

Myth 7: “Peeling the cap removes the poison”

False. Poisonous and deadly species stay just as poisonous after peeling.

Myths about appearance

Myth 8: “Young, fresh mushrooms are safe”

False. VAPKO notes that poisonous mushrooms are just as poisonous young as fully grown. Very young mushrooms are also harder to identify, so experienced foragers usually leave them.

Myth 9: “White mushrooms are harmless”

False. The destroying angel and several small white funnel mushrooms are poisonous.

Myth 10: “Mushrooms with pink gills are edible”

False. The livid pinkgill and the yellow stainer, a poisonous relative of the field mushroom, can have pink gills too.

Myth 11: “A ring on the stem means it’s safe”

False. The deadly death caps have rings.

Myths about place and season

Myth 12: “Mushrooms from fields and meadows are safe”

False. Some small dapperlings and the yellow stainer grow in grassland too, and both are poisonous.

Myth 13: “Spring mushrooms or late-autumn mushrooms are safe”

False. The spring amanita, which appears in spring, is deadly. The green death cap, the fly agaric and the livid pinkgill are all still around in late autumn.

Myth 14: “Mushrooms growing on living trees are edible”

False. The poisonous jack-o’-lantern mushroom grows on trees.

Myths about people and technology

Myth 15: “An app will tell me” or “Some people can eat anything”

Both false. Austria’s health portal considers apps and AI unsuitable for mushroom identification, and the German Federal Institute for Risk Assessment (BfR) says apps often can’t give an unambiguous identification. We explain why in Mushroom Identification App: Why a Photo Isn’t Enough. As for tough stomachs, VAPKO is blunt: nobody has ever withstood the toxins of poisonous or deadly mushrooms.

Folk rules fail both ways

Here’s a twist that shows why rules of thumb are so unreliable: they also wrongly condemn good mushrooms. VAPKO points out that the shaggy ink cap grows on dung and is edible, that several slimy boletes are edible, and that milkcaps with orange-red milk are edible too. Shortcuts get it wrong in both directions. Only knowing the species gets it right.

How many mushrooms are actually poisonous?

Fewer than you might think, which is part of what makes foraging so rewarding. The DGfM estimates that Germany has about 14,400 mushroom species (in German):

• About 200 are edible.
• About 150 are poisonous, and 10 of those are classed as deadly.
• The rest count as inedible: they taste bad, are indigestible, too small or too hard, or nobody yet knows whether they’re toxic.

So “not on the poisonous list” doesn’t mean “edible”. It does mean you only need to know a handful of species really well to enjoy safe, happy foraging.

What actually works

1. Learn one species at a time from a current regional field guide, a guided walk or a course, together with its poisonous look-alikes.
2. Check every feature: cap, gills or tubes, stem, ring, base, flesh, smell, habitat and season. If one detail doesn’t fit, the answer is no.
3. Bring the whole mushroom when you want it identified, with its base intact.
4. Have it checked in person by a mushroom expert. Find one in Austria, Germany or Switzerland (all in German).
5. If in doubt, leave it out. The forest will still be there next weekend.

For the full picture, from what to bring to how to cook your finds, read our mushroom foraging tips for beginners.

What to do if someone feels unwell

Act quickly, even if you’re not sure the mushrooms are to blame. With the most dangerous poisonings, symptoms may not appear until 6 to 24 hours after the meal (in German). Call for help, keep any leftovers, tell everyone who shared the meal, and don’t try home remedies such as inducing vomiting or drinking milk.

• Austria: ambulance 144, Poison Information Centre (VIZ) +43 1 406 43 43, open 24 hours for emergencies
• Germany: emergency 112, list of regional poison centres
• Switzerland: Tox Info Suisse on 145, open 24 hours
• Elsewhere in Europe: emergency 112, poison centres in Europe (in German)

Prefer mushrooms without the guesswork?

At Stoff’n we grow our mushrooms, so we always know exactly which species is in the basket. With a mushroom growing kit you can enjoy that certainty at home, and then try something from our mushroom recipes.

This article is general information and can’t replace an in-person check by a qualified mushroom expert. Picking and eating wild mushrooms is at your own responsibility. Last updated: November 2026.