Honey Fungus Galore

There is honey fungus everywhere I look this autumn, and that’s a very bad news for the trees.

I first noticed its abundance in a small local woodland near our house mid September, then saw lots of it again during a few days stay in Glen Affric last month, but it was the quantity of it encountered on a walk along Allan Water above Bridge of Allan a week ago that gave me a real pause for thought, it was everywhere I looked that morning.

Honey fungus is incredibly destructive, and by the time the fruit bodies appear, the tree is a gonner, even if it externally looks fine, there is nothing much that can be done.

It’s not just here, I gather from an article on the subject in the Guardian today. The mycologist there blames it on the summer drought stressing the trees and so weakening their defences — I am not wholly convinced by this explanation, as we have not had a proper drought in our area. A few longer dry spells here and there, yes, but not really something we have not seen in recent years, and the honey fungus explosion seems out of all proportion to this.

But my perception of how dry the summer was is, I suspect, not that relevant, for we have now had a string of hottest years on record. Individual tree species are adapted to only a very narrow temperature window, and given we have already exceeded the 1.5C of warming, I suspect many of our trees are now finding themselves beyond their ‘comfort zone’ — I reckon it is this cumulative effect, rather than just a single dry summer, that is at play here, and if that is the case, we might be hitting a tipping point we didn’t even know until now existed!

Most of the specimen I see are, AFAICT, Armillaria ostoyae, the Dark Honey Fungus, rather than Armillaria mellea; I have not been collecting any samples (really quite keen not to spread the spores), nor taking many pictures, but the dark scales on the ring that distinguish this species are clearly visible in the image below, even in these old specimen: