Giant ash bracket.
Ash, beech, false acacia.
Hornbeam, horse chestnut, oak, plane, poplar, sycamore.
Found at the base of the tree and on surface roots. Rarely up the stem to 2-3m.
Perennial. Tough and woody. Can become very large (and heavy). Found singularly or abundantly. Begins as a beige-white mass. Bracket forms to a beige-brown to green (or brown-purple) upper surface (sometimes algal-stained), often rimmed beige-white to yellow, and with a white pore layer beneath. Ends of such brackets may bend slightly under pressure. Spore abundant and white. Flesh beige. Can exude a milky liquid when cut. Tube layer darker brown. Senescent brackets darken and become a dark brown-green and often remain attached to the tree.
Attributed to a simultaneous white rot of the wood – can cause the wood to shear at the roots and butt. High-profile cases have made this fungus much maligned. Considered pathogenic though also able to act saprotrophically. Where targets exist, investigations into stem hollowness and stability may be required. Larger brackets indicate potentially long-standing decay.