Sapwood exposure and the fungus Inonotus hispidus

Because the shaggy bracket (Inonotus hispidus) is a sapwood-exposed fungal pathogen, it requires a wounding site to be able to successfully gain entry into a host. In this instance, we can observe how utility pruning has enabled this fungus’ spores to enter and colonise a Swedish whitebeam (Sorbus intermedia), and subsequently produce two sporophores on the same side of the structure. Without doubt, this will lead to a decline in the health of the individual over time, and because many other whitebeams down the road also have received similar pruning operations and are visibly struggling (lots of deadwood), I wonder whether they too are infected. Combined with mower damage at the base, which has led to some other individuals being visibly colonised by Ganoderma sp. at the base of the stem, there is little in the way of a bright future for these whitebeams, it appears.

On the left hand side of the crown, we can observe some utility pruning. Such pruning is the bane of many trees, and can unfortunately severely limit where trees can exist within the urban setting.

Beneath the pruning points, these two sporophores reside. If I were a betting man, I would say the pruning caused such fungal colonisation.

A closer look at these fungi, which have become coal-like in texture and appearance after becoming inactive. Fresh sporophores of this species are much nicer in appearance, though their persistence on the tree and at its base (sometimes for many years) allows us to readily identify where this species has colonised.

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