Stem and scaffold limbs (often on or adjacent to wounds) – be certain to look for fallen blackened fruiting bodies around the base of the tree and still attached (sometimes only partly) to the tree.
Annual . Found growing often in clusters (tiers / decks). Fruiting bodies begin a yellow-orange mass and quickly develop into brackets that are orange-gold on the upper surface and a little hairy (hispid). Pore layer off-white. Flesh and tubes brown. Spore yellow (look for spider webs beneath that are stained yellow). Maturing brackets exude yellowish liquid on the underside. Can become quite large. Fruiting bodies blacken in autumn and sometimes fall from the tree.
Inonotus hispidus (found often on apple, ash, whitebeam and walnut).
Currently, there exists a lack of direct research on its pathogenicity, though this fungus has sometimes been associated with the failure of large limbs that have been subject to a simultaneous white rot (photo d). More research has been undertaken on Inonotus hispidus, which can cause limb failure and has the ability to act pathogenically.