The New Forest has a great number of very mature oak and beech trees which are in varying stages of decay, but all can be excellent hosts to this large perennial shelf or bracket fungus (Ganoderma australe).
It can attain a considerable size with its semi-circular shape often reaching well over 60 cm across when it is many years old. It grows out from trunks or stumps and amazingly, is nearly as hard as the wood from which it grows. It is probably the most common and largest of the six Ganoderma species in this country and can fruit on living or dead trees.
When first emerging from the wood, it appears as a very hard white lump which will, over several years, become completely brown on top, as it expands into the mature bracket.
Each year as it increases in size from a creamy white margin of new growth, a new ridge will grow, similar to the annual growth rings of a tree, but on the top surface. It tends to grow fairly low down, singularly or several in tiered layers. The cocoa coloured spores are often very visible because when they drop downwards from the bracket in huge numbers, and are dispersed by the wind, they may stick to the surrounding vegetation, tree trunk and even to the top of the bracket itself.
During the long lifespan of this fungus, the once standing host tree may fall over, so the fungus has the ability to produce a new shelf from its old one, to correct its orientation. This is vital if the fungus is to continue to disperse spores efficiently.