Mushroom identification
Nearly every serious poisoning is somebody eating one thing while believing it was another.
So this is organised in pairs rather than species: the one you are looking for, the one that resembles it, and the features that separate them, in the order you should check.
- look-alike pairs
- 16
- 7 of them lethal
- specimen sheets
- 43
- 8 that can kill you
- poisoning syndromes
- 8
- 2 with a delayed onset
- methods, kitchen and grow
- 15
- the zero-risk route
The one thing worth knowing
The poisonings that hurt fastest are the ones you recover from.
Mushroom poisonings are classified by syndrome, and the first question a clinician asks is how long after the meal the symptoms began. The answer sorts them almost perfectly, and it sorts them the wrong way round from instinct.
Left of the line, under six hours. Almost always a gut irritant. Violent, frightening, and usually over inside a day.
Right of the line, after six hours. Amatoxin, gyromitrin or orellanine. An organ is already being destroyed. This is an emergency even if the person feels fine.
One qualification, and it matters enough to state on the chart rather than in a footnote: a mixed wild meal can produce an early irritant reaction that hides a late amatoxin one. An early onset is reassuring only if you are certain a single species was eaten.
The pairs
16 pairs. 7 of them will kill you.
Chanterelle
mistaken for
Jack-o'-lantern
Illudin S
DeadlyTrue morel
mistaken for
False morel
Gyromitrin, which the body converts to monomethylhydrazine
DeadlyHoney mushroom
mistaken for
Deadly galerina
Amatoxins, the same class as in the death cap
DeadlyPuffball
mistaken for
Amanita button
Amatoxins
SeriousShaggy parasol and parasol
mistaken for
Green-spored parasol
Unidentified gastrointestinal toxins
DeadlyMeadow mushroom
mistaken for
Destroying angel
Amatoxins
DeadlyParasol
mistaken for
Deadly dapperling
Amatoxins, the same compounds as in the death cap
DeadlyChanterelle
mistaken for
Deadly webcap
Orellanine
SeriousHoney mushroom
mistaken for
Sulphur tuft
Unidentified gastrointestinal toxins, with liver damage reported at high doses
SeriousFairy ring champignon
mistaken for
Ivory funnel
Muscarine, at a far higher concentration than the fly agaric contains
SeriousOyster mushroom
mistaken for
Angel wings
An unidentified compound affecting the brain, likely an amino acid
SeriousPuffball
mistaken for
Common earthball
Unidentified gastrointestinal toxins
SeriousSt George's mushroom
mistaken for
Livid pinkgill
Unidentified gastrointestinal toxins
UnpleasantShaggy mane
mistaken for
Common inkcap
Coprine, which blocks alcohol metabolism in the way the drug disulfiram does
DeadlyMatsutake
mistaken for
Smith's amanita
Allenic norleucine and related compounds
SeriousCaesar's mushroom
mistaken for
Fly agaric
Ibotenic acid and muscimol
The key
Answer questions about the thing in your hand.
A dichotomous key is how identification is actually done, and it teaches the order in which features matter, which no list of species pages can. Turn it over, look at the base, take a print. Each answer narrows the field and names what could still kill you.
Start the keyStep 1
Turn it over. What is on the underside of the cap?
- Blades or ridges
- A sponge of tiny pores
- Downward-hanging spines
- Nothing. It is a closed ball
and three more
Spore print colours
The cheapest test there is, and it settles several of these outright.
A green print means the most commonly eaten poisonous mushroom in North America and essentially nothing else. A rusty print on wood separates the honey mushroom from the deadly galerina growing beside it. It costs a sheet of paper and a night, which is exactly why people skip it.
How to take oneOnce you know what it is
43
specimen sheets
The species, as specimen sheets
Cap, underside, stem, flesh, spore print, habitat, in the order you actually examine a mushroom. Each one names the single character that does most of the work.
8
techniques
Ruined in the kitchen, not the woods
Wild mushrooms are spoiled far more often by washing them, crowding the pan and undercooking them than by misidentification. Every entry gives the reason rather than the instruction.
7
grow methods
The only route with no risk at all
You know what it is because you inoculated it. From a kit you cut open and mist, to shiitake logs that crop for six years, to a wood chip bed that needs nothing.
Things that are not true
Every folk test for poisonous mushrooms is worthless.
Poisonous mushrooms tarnish a silver spoon.
Complete fiction with no chemical basis whatsoever. Amatoxins do nothing to silver.
If you can peel the cap, it is safe.
The cap of a death cap peels easily.
Animals eat it, so it is safe for people.
Squirrels, slugs and deer eat amanitas without harm. Their metabolism is not yours.
Poisonous mushrooms taste bad.
Survivors of death cap poisoning frequently describe it as delicious. Taste is not a warning system for a toxin that takes twelve hours to announce itself.