Armillaria Root Rot

Armillaria root rot, caused by fungi in the genus Armillaria, affects trees, shrubs, vines and even herbaceous plants throughout the world, in both tropical and temperate climates. These endemic fungi typically act opportunistically, killing weakened trees, and are frequently a sign of natural stand aging and not a serious concern.  However, Armillaria fungi can also infect and kill healthy trees, or make them more susceptible to other pathogens and insect pests.  Armillaria root rot is most problematic when combined with other stressors and thus changing climate, land use changes, and increasing invasion by pathogens and insects, increases its potential to harm forest trees.