A black fungus with white fruiting bodies, commonly called Brittle CInder

One of the Deusta fungi

Names: Kretzschmaria deusta, Brittle Cinder, Carbon Cushion, Ustulina deusta, Discosphaera deusta, Hypoxylon deustum, Hypoxylon magnosporumLloyd, Hypoxylon ustulatumBull., Nemania deusta, Nemania maxima, Sphaeria albodeusta, Sphaeria deusta, Sphaeria maxima, Sphaeria maxima, Sphaeria versipellis, Stromatosphaeria deusta, Ustulina deusta, Ustulina maxima and Ustulina vulgaris.
Hosts: Broadleaves
Attacks: Heartwood, roots and stem base
Consequences: Wood becomes brittle leading to sudden fracture.