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Armillaria infection on trees

Armillaria is a widespread native fungus that causes roots to decay on many native and non-native trees. Mushrooms appear (see right photo) only for several days making diagnosis difficult. Bark on infected trees can die and crack (such as on the crapemyrtle below) and a white fungus mass may be visible around the dead bark (see top of photo). The canopy of the tree can die back such as the infected live oak shown below. Dead branches on this oak are more than 5 inches in diameter and the tree is hazardous.

Armillaria infected tree canopy