Country diary: A heady mix of sex and drugs for this wasp

·2 min read

It has begun to feel autumnal here. Today, this tree-lined footpath was strewn with fallen leaves, shed during the heatwave, but enlivened by a blaze of end-of-summer wild flowers: purple willowherb and knapweed; yellow loosestrife, tansy and ragwort; pink umbels of angelica.

The plant we had come to look for – broad-leaved helleborine, with its demure greenish-purple flowers – might be more subdued, but it has an intoxicating sex life. Epipactis helleborine likes edges and verges, embankments and cuttings. This disused railway line, linking former pit villages, is all edges. It skirts woods and old quarries, sheep pastures and meadows where curlews nest, snaking downhill from Stanley Crook towards Esh Winning.

A century ago, the valley would have been filled with the sounds of colliery hooters, squealing pulleys and iron wheels on rail tracks. The gradient was too steep for locomotives, so coal wagons were hauled on cables, up the fearsome Stanley Incline to the stationary engine on the hilltop. Today it was quiet, just the leaves rustling in the trees.

We had almost reached Waterhouses when we found the first helleborines, in dappled shade among brambles. Most had finished flowering early, withered by the searing summer heat, but one was still in peak condition, flaunting its charms to a wasp.

Other insects visit these helleborines, but it relies on wasps for pollination. Like all native orchids, it doesn’t just dust visitors with pollen, it sticks its whole male sexual organ, the pollinium, on to its visitor’s face, to be carried between flowers. The head of a wasp is just the right size and shape to pick up a pollinium when it forces its way in, reaching for nectar.

We watched the whole performance: a bewildered, stumbling wasp, unsuccessfully trying to remove its pollinium burden, but unable to resist the lure of another floral visit. It had been drugged by the plant’s nectar. Some research suggests that it contains fermented alcohol that stupefies visitors; other evidence indicates that it’s laced with opiates.

I gave the wasp a cautious poke, wary of an aggressive response. Instead, it fell to the ground and waved its legs in the air. Completely stoned, a martyr to sex and drugs.

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