Tree fungus

Silver leaf disease (Stereum purpureum)

Fruiting bodies: Frequently only noticeable once the tree has died completely.
Wood decomposition:
white rot
Effect: The fungi enters the tree through wounds. The violet colored fruiting bodies form first on the dead wood. Sure identification characteristic is the metallic lead colored discoloration on the leaves. Infected trees die off. The fungi spreads through spores and across the ground. Therefore, a disinfection of the ground would be recommended before planting again.
Situation should be evaluated.