and life cycle—Annosus root
Annosus root disease infects through roots and primarily affects
conifers in areas where they grow naturally. Susceptible hosts,
primarily pines, are often killed within several years. Other common
hosts—true firs, Douglas fir, incense cedar, and hemlock—are
usually not killed outright, but develop decay in heartwood that
increases susceptibility to insect attack and wind damage.
The fungus can survive for several decades in the roots of dead
hosts, so trees are often killed in a gradually expanding clump
as nearby plants are infected through root contact. The fungus
spreads long distances by airborne spores. Spores can germinate
when they contact a freshly cut stump, creating a new infection
center as the fungus spreads down through the stump into roots
that contact nearby living trees.
of annosus root disease