Size

Very small (<3 cm)

Q: But what about young honey fungus or chanterelles — they can be 2 cm too?

Young specimens (buttons) of large or medium mushrooms can indeed be small. But the size category refers to the ADULT, fully opened mushroom. An adult honey fungus or chanterelle will grow to 5-10 cm. An adult bonnet, on the other hand, will stay 2 cm forever. That is exactly why mushrooms are identified from opened, mature specimens.

Very small (<3 cm) — mushrooms with the trait «Very small (<3 cm)»

The category of mushrooms with a cap diameter of up to 3 centimeters is the most numerous, the hardest to identify and the least interesting for cooking.

In American mycological literature (following David Arora), there is even a special joking acronym for such mushrooms — LBM (Little Brown Mushrooms). It is a catch-all term for thousands of species of tiny, inconspicuous mushrooms on thin stems that grow in grass, on rotting leaves or on wood.

22 species in the database.

What counts as "very small"?

1. Bonnets (Mycena): Fragile, translucent woodland mushrooms that grow on fallen leaves, needles or old cones. Their cap is often no more than 1-2 cm.

2. Funeral bell (Galerina marginata): This is the main reason to be careful with LBMs. It is usually 1.5 - 3 cm across and looks like a small, innocent toadstool on a stump, but it contains the same deadly poison (amatoxin) as the death cap.

3. Psilocybe: Many hallucinogenic species are extremely small (1-2.5 cm).

4. Mottlegills (Panaeolus) and ink caps: They grow on soil or animal dung and have wire-thin stems and tiny caps.

A mycologist's golden rule

For the average forager, there is only one rule for mushrooms smaller than 3 cm: you don't pick them.

- First, they have no culinary value. To gather a portion for soup, you would need several hundred of these little mushrooms.

- Second, they are incredibly hard to tell apart without a microscope (to look at spore shape). It's easy to confuse a harmless bonnet with a deadly Galerina.

Questions and answers

But what about young honey fungus or chanterelles — they can be 2 cm too?

Young specimens (buttons) of large or medium mushrooms can indeed be small. But the size category refers to the ADULT, fully opened mushroom. An adult honey fungus or chanterelle will grow to 5-10 cm. An adult bonnet, on the other hand, will stay 2 cm forever. That is exactly why mushrooms are identified from opened, mature specimens.

Sources

1.Зерова М.Я. та ін. Визначник грибів України. 1979
2.Roger Phillips. Mushrooms (Roger Phillips)
3.David Arora. Mushrooms Demystified
4.Index Fungorum