You Can't Tell a Poisonous Mushroom by Looking — Wild Mushroom Safety in Autumn
Bright colours mean poison? Bug bites mean safe? Why these myths are dangerous, which autumn mushrooms cause most poisonings, and what to do if one is eaten.
September and October bring the most wild mushroom poisonings in Korea. After autumn rain, mushrooms appear all at once in forests, fields, lawns and around graves — just as people head out for hikes and family visits.
Korea has 2,389 recorded mushroom species. Only 418 (about 17%) are confirmed edible and 249 are known to be poisonous. For the remaining 1,700 or so, nobody yet knows whether they are safe to eat.
Every one of these rules of thumb is wrong
- Bright colours mean poison, plain ones are edible — the deadliest species, the destroying angel, is pure white.
- If it tears lengthwise, it's edible — most poisonous mushrooms tear lengthwise too.
- If insects or slugs ate it, it's safe — toxins that kill people can be harmless to them.
- A silver spoon turns black near poison — mushroom toxins don't react with silver.
- Cooking or drying removes the poison — amatoxins, the toxins in deadly Amanitas, survive heat.
The same species can look very different depending on where it grows, the weather and its age, so even experts don't identify mushrooms by appearance alone. The same goes for photo ID apps: no app, GreenPic included, can tell you a wild mushroom is safe to eat.
Poisonous mushrooms to watch for in autumn
- Destroying angel and fool's mushroom (Amanita virosa, A. verna): all white and easy to mistake for edible species. Their toxin destroys the liver; a small amount can kill.
- Amanita subjunquillea: a yellowish, deadly Amanita and one of the main causes of fatal mushroom poisoning in Korea.
- Tsukiyotake (Omphalotus japonicus): easily confused with oyster and shiitake mushrooms. Causes severe vomiting and diarrhoea.
- Poison fire coral (Trichoderma cornu-damae): red, finger-shaped. Extremely dangerous to eat, and even touching it can irritate the skin.
- Sulphur tuft (Hypholoma fasciculare): grows in clusters on stumps, like edible brick caps.
- Wood pinkgill (Entoloma rhodopolium): a plain grey-brown mushroom often mistaken for an edible one; a frequent cause of group poisonings.
- Common ink cap (Coprinopsis atramentaria): eaten with alcohol, it causes flushing and a racing heart.
Late symptoms are the most dangerous
The deadliest Amanitas cause no symptoms for 6 to 24 hours. Vomiting and diarrhoea follow, then a day or two when the person seems to recover — while the liver and kidneys are being damaged. Deciding you feel better and skipping the hospital is the biggest risk.
If someone has eaten a wild mushroom
- Call emergency services (119 in Korea) or go to an emergency room right away, even without symptoms.
- Bring any leftover mushrooms, cooked food or photos — they help doctors identify the toxin.
- Everyone who shared the meal should be checked.
- Don't lose time on home remedies.
The only reliable prevention is not eating mushrooms you picked in the wild. Buy cultivated mushrooms from a shop or market.
The mushroom pages below show what each species looks like, which edible mushrooms it resembles and its symptoms. Learn them to avoid them, not to eat them.
Plants in this article
- Destroying angel
- Fool's mushroom
- East Asian death cap
- Tsukiyotake
- Poison fire coral
- Sulphur tuft
- Wood pinkgill
- Common ink cap