What is "armillaria"

n. Any of the genus (taxlink Armillaria genus noshow=1) of parasitic fungus; a honey fungus.

Honey fungus, or Armillaria is a genus of parasitic fungi that live on trees and woody shrubs. It includes about 10 species formerly lumped together as A. mellea. Armillarias are long lived and form some of the largest living organisms in the world. The largest organism (of the species Armillaria solidipes) covers more than in Malheur National Forest and is more than 2,400 years old. Some species of Armillaria display bioluminescence, resulting in foxfire.

Armillaria can be a destructive forest pathogen. It causes "white rot" root disease (see Plant Pathology section) of forests, which is distinguishes it from Tricholoma, a mycorrhizal (non-parasitic) genus. Because Armillaria is a facultative saprophyte, it also feeds on dead plant material, allowing it to kill its host, unlike parasites that must moderate its growth to avoid host death.

In the Canadian Prairies (particularly Manitoba), Armillaria is not referred to as “honey fungus” but instead often as pidpenky , meaning “beneath the stump” in Ukrainian.