Amylostereaceae usually infest only dead or cut down conifer wood.
Three species – A. areolatum, A. laevigatum and A. chailletii – may also establish a symbiosis with wood wasps (Siricidae), which beside freshly logged trees also infest living trees and infect them with fungi.
Symbioses have been recorded with several species: Sirex noctilio, S. juvencus, S. nitobei, S. cyaneus, S. edwarsii, S. nitidus, and, in Japan, Urocerus antennatus and Xoanon matsumurae.
Wasps of the genera Sirex and Urocerus store oidia (the hypha of fungi split up to spores) in special abdominal organs.
The wood wasps infect trees by splashing a phytotoxic secretion below the bark and at the same time injecting fungal spores into the hole.
The secretion weakens the tree and temporarily diminishes its immune system, whereby the fungus can spread along the xylem.
The infection with Amylostereaceae fulfill two functions for the wasps: it provides the larvae food, because the white rot softens the wood; at the same time, the mycelia of the fungi serves as food for the larvae.
After the larvae pupate, it absorbs the mycelia of the Amylostereaceae into its body to oviposit together with its eggs.
The fungus benefits from the symbiosis as it spreads faster and more effectively than through airborne spores and furthermore does not need to develop fruit bodies.
 A. ferreum is the only Amylosterum species that has not been associated with any woodwasps.
Amylostereaceae usually infest only dead or cut down conifer wood. Three species – A. areolatum, A. laevigatum and A. chailletii – may also establish a symbiosis with wood wasps (Siricidae), which beside freshly logged trees also infest living trees and infect them with fungi. Symbioses have been recorded with several species: Sirex noctilio, S. juvencus, S. nitobei, S. cyaneus, S. edwarsii, S. nitidus, and, in Japan, Urocerus antennatus and Xoanon matsumurae. Wasps of the genera Sirex and Urocerus store oidia (the hypha of fungi split up to spores) in special abdominal organs. The wood wasps infect trees by splashing a phytotoxic secretion below the bark and at the same time injecting fungal spores into the hole. The secretion weakens the tree and temporarily diminishes its immune system, whereby the fungus can spread along the xylem. The infection with Amylostereaceae fulfill two functions for the wasps: it provides the larvae food, because the white rot softens the wood; at the same time, the mycelia of the fungi serves as food for the larvae. After the larvae pupate, it absorbs the mycelia of the Amylostereaceae into its body to oviposit together with its eggs. The fungus benefits from the symbiosis as it spreads faster and more effectively than through airborne spores and furthermore does not need to develop fruit bodies.  A. ferreum is the only Amylosterum species that has not been associated with any woodwasps.
Amylostereum