The series of grooved lines in the tree trunk looks like a preconceived design and reminds me of work by the wonderful Norfolk artist Roger Ackling. From a central channel, incised vertically into the wood, a further 60 galleries spread horizontally on each side.
In truth, this pattern charts the lives of two generations of a remarkable insect. The vertical chamber was cut by a mother beetle, and at intervals down her linear home she deposited 120 eggs. Tiny larvae hatched from these, and set out gnawing their separate ways from the maternal chamber. You can see that, as the offspring progressed outwards, they also grew, because the calibre of their corresponding groove also expands.
I want to say that the finished thing resembles a pair of spreading wings, but am I running a risk of suggesting that it has visual appeal? Because it was made by one of two notorious creatures, the small or large elm bark beetle. The second name has meaning only in relative terms, given that its owner measures 5mm, while its sibling is just 2mm. Their shared works, however, are immense.
Across Europe, Asia and America, they have helped to fell hundreds of millions of trees over the last century. To get at the inner workings of this monumental destructiveness, we should name the key accomplice in so-called Dutch elm disease. It is a fungus (called Ophiostoma, the “snake-mouth”) that works symbiotically with these insects.
The beetles transfer Ophiostoma spores, carrying them in a purpose-made pouch called a mycangia, and in return the fungus detoxifies the elms’ defensive chemicals and provides its insect vectors with nutrients. Even more extraordinary is that the fungus stimulates the tree to produce chemical signals that recruit even more beetles. In short, the elm advertises to the agents of its own nemesis.
From the viewpoint of one who loved elms – like John Constable, whose paintings are now a key repository of Britain’s former elm heritage – the whole double act could look brutal, even nihilistic. Yet from the amoral perspective of life’s unfolding processes, that same exquisitely attuned partnership surely embodies something that is a kind of living beauty.
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