Hypoxylon Oak Canker

Biscogniauxia atropunctata

A species of fungus within the Xylariaceae family.

Hypoxylon Oak Canker a.k.a. "Biscogniauxia Dieback" is a white-rot fungus that infects primarily Oak (Quercus sp.) trees, usually following a period of stress like a drought. The fungus will eventually cut off the supply of water and nutrients to the tree by destroying the sapwood (nutrient-conducting tissues).