Others root disease

Armillaria (Armillaria mellea) is a root pathogenic fungus of hardwoods.

Armillaria root infections cause the affected tree to wither and gradually die. Armillaria infections are characterised by the presence of whitish mycelium under the bark at the collar and roots and on dead roots of flattened brown strands (called rhizomorphs, Figure 1). Fruiting bodies, in the form of carpophores, appear in autumn in clumps at the base of infected trees.

In chestnut, armillaria is observed on weakened trees and in humid sites where ink is often present.