Heterobasidion annosum - a notorious, tree-killing bracket fungus

We found this impressive specimen of the root rot bracket fungus Heterobasidion annosum in Hamsterley Forest at the weekend. The roots of the Norway spruce that it was growing on will have been largely destroyed by the time the fungal fructification reaches this stage.

The bracket was actively releasing spores - notice the dense white covering on the ground under the bracket. They are often dispersed by soil animals.

Root rot is one of the most damaging tree pathogens and the surrounding trees, as well as this one, are likely to be fatally infected.