You don’t always know when the magic starts, but there is a moment when it enters your consciousness with a flourish. Trotting down from the headwaters of the River Derwent, we found ourselves entering a narrow valley of gold and bronze, but I was still thinking about the moors we’d just left. Their scale and grandeur are breathtaking, but intense grazing over millennia has left this landscape at the end of its natural tether, wearied and sombre. Here, though, suddenly all was light. The explanation was in the name for this spot: Oaken Bank.
Unlike so many of the cloughs that feed the nascent river, this valley remains busy with oaks, as well as birch and rowan, their leaves fireworks, some of whose sparks had settled on the path in heaps we kicked through.
Then something caught my eye. Squarely in the middle of a yellowing oak leaf on the ground was something that looked like an apple, a beeley pippin maybe, yellow but flushed red on one side, only smaller, like a scale model, just 2cm in diameter. When I stooped to gather it up, it came loose and dropped into my hand, and I realised it had been physically attached to the leaf. It was clearly an oak gall, and its apple impersonation made me think first of the gall wasp, Biorhiza pallida. This being late October, that wasn’t likely. It was instead the work of the cherry gall wasp, Cynips quercusfolii. Inside this little globe was a larva, part two of a complex reproductive cycle. In a few weeks, a wasp will emerge from this gall to lay eggs on the oak’s bark in a process of parthenogenesis. Wasps from those eggs will mate and the females then lay more eggs on the underside of next summer’s leaves.
All that complexity in the palm of my hand, like the golden valley, also felt like magic. Sobering, then, to recall that plans to flood this scrap of paradise for a reservoir have only recently receded.
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