BT: [[fungi]] / [[parasitic fungi]] / [[saprotrophic fungi]]
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# *Armillaria* (genus)
*Armillaria* fungi are among the largest organisms in the world.[^1] The largest known specimen (an *A. ostoyae*) covers more than 8.8 km² in [[Oregon]], [[USA]], and is somewhere between 2,000 and 8,000 years old.[^2]
Some species of *Armillaria* display [[bioluminescence]].[^3]
*Armillaria* fungi can be a destructive forest pathogen as ‘white rot’ root disease. While feeding on dead plant material, *Armillaria* can kill their host with little negative effect to themselves.[^4] (See also: [[parasitic fungi]].)
[^1]: Sheldrake, *[[Sheldrake, Entangled Life, 2021|Entangled Life]]*, p. 4.
[^2]: Sheldrake, *[[Sheldrake, Entangled Life, 2021|Entangled Life]]*, p. 4; ‘Armillaria’, Wikipedia, last edited 4 April 2026, 22:33 (UTC), [https://en.wikipedia.org/wiki/Armillaria](https://en.wikipedia.org/wiki/Armillaria).
[^3]: ‘Armillaria’, Wikipedia, last edited 4 April 2026, 22:33 (UTC), [https://en.wikipedia.org/wiki/Armillaria](https://en.wikipedia.org/wiki/Armillaria).
[^4]: ‘Armillaria’, Wikipedia, last edited 4 April 2026, 22:33 (UTC), [https://en.wikipedia.org/wiki/Armillaria](https://en.wikipedia.org/wiki/Armillaria).