# Honey fungus (Armillaria)

**Armillaria* species*

**Known today as.** Honey-colored clusters on stumps and trees, from black cords, the “shoestrings,” that spread beneath the bark.

Kind: Fungus  
Poisoning: Gastrointestinal irritants (https://thethinkingpress.org/materia-medica/poisons/gastrointestinal)

> **Caution.** Never eat raw.

## What was it used for?

Edible when well cooked; raw it causes illness.

## What does modern science say?

A killer of trees in gardens and forests.

## Pharmacognosy and toxicology

- **unknown**: 

**Mechanism.** Edible thoroughly cooked; mildly poisonous raw, and it can cause sickness when eaten with alcohol.

**Dose.** Raw caps, or caps eaten with alcohol.

**Standing.** Prized in Ukraine, Russia, Poland, Germany and elsewhere in Europe, eaten thoroughly cooked; the organism is among the largest living things, one clone in Oregon covering about nine square kilometres.

## What lore surrounds it?

Some species make the wood they rot glow in the dark: the “foxfire” that lit the instrument needles of the *Turtle*, the first submarine used in war, in 1775. Benjamin Franklin is often said to have suggested it, but the letters show he was asked only for another light when the cold put the foxfire out. A single *Armillaria* in Oregon covers some 965 hectares (about 2,400 acres), among the largest living things on earth.

## Sources

- Ferguson, B. A., et al. (2003). Coarse-scale population structure of pathogenic *Armillaria* species. *Canadian Journal of Forest Research* 33: 612–623.
- Wikipedia contributors. “Armillaria.” *Wikipedia, The Free Encyclopedia*. en.wikipedia.org/wiki/Armillaria (read 2 October 2026).
- Wikipedia contributors. “Armillaria ostoyae.” *Wikipedia, The Free Encyclopedia*. en.wikipedia.org/wiki/Armillaria_ostoyae (read 2 October 2026).
- Wikipedia contributors. “Foxfire.” *Wikipedia, The Free Encyclopedia*. en.wikipedia.org/wiki/Foxfire (read 2 October 2026).
- Wikipedia contributors. “Turtle (submersible).” *Wikipedia, The Free Encyclopedia*. en.wikipedia.org/wiki/Turtle_(submersible) (read 2 October 2026).

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*Honey fungus.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-03. The Thinking Press. https://thethinkingpress.org/materia-medica/honey-fungus

Historical description, not medical advice.