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ARTIST’S BRACKET FUNGUS, Ganoderma applanatum

The bark of a tree is its first defence against damage. It’s living tissue, unlike the older heartwood at the tree’s centre. But if the bark becomes wounded, say by fire or frost, deer or man, fungal spores can enter, slowly rotting away the heartwood, and in time perhaps hollowing the trunk entirely. Weakened, the tree may topple to give opportunity for new growth, be it tree or insect – see for example the lifecycle of the stag beetle, Walk 17.

One type of such fungal invasion gives rise to the artist’s bracket fungus, which might well be seen on older beech and hornbeam trees in the Forest. As the bracket grows each year (it will live at least as long as the afflicted tree, so quite likely a decade or more), it lays down rings, mimicking the tree’s behaviour. The fungus itself is a ‘white rot’, turning the heartwood moist and spongy.

The artist’s bracket fungus is immune to the forager’s knife. Even if it could be prised off, it is rock hard, and no matter what the cooking would break teeth before it could do any damage to the stomach or brain. It can, however, be carved, hence the name.