Below the downs, across Milking Parlour and Trenchfields – two fields named during the second world war – the oilseed rape has been harvested, leaving the fields like folds in a discarded tweed jacket. The unharvested standing crop next door is blackened by desiccation from glyphosate, a last chemical dousing to make the crop more palatable and even for the combine. The evening before, we watched the combine at work. At 9pm, and with several more hours of cutting, threshing and carting to do before forecast rain, the machine was an awesome sight. Coming up the tramlines with the roar of a billion bees, lamps blazing through a swirling cloud of apocalyptic grey dust, it set our hearts racing. I wondered what the soldiers rehearsing D-day in these fields – or the dairywomen and workers at harvest – would recognise here, when these fields took on their modern incarnation. The earliest combine harvester (a secondhand Massey Harris Bagger, driven by a woman) wasn’t employed here until 1953. And oilseed rape was unfamiliar until the 1970s and 80s (although it was grown from the 19th century to produce lubricating oil for steam engines and oilcake as a byproduct for animal feed). Today, rapeseed is ubiquitous in our kitchen cupboards as vegetable oil, despite being a tricky crop to grow; an array of fungicides, herbicides and pesticides is required to keep away the cankers, weeds and cabbage stem flea beetle. What might surprise them the most are the buzzards and kites (rare or extinct in their time) that have gathered to glean injured or exposed prey from the brassica stubble. I watch seven kites floating, tilting, the notch on the inside joints of their wings giving them an elegantly ragged insouciance. Bulkier, darker buzzards patrol below them, skimming the ground. A little copse reverberates with the plaintive mewing of their offspring. On the field margin, knapweed seedheads, emptied of their down, shine like tinfoil, smoothed by the back of a teaspoon into silver suns. They match the shellac gleam of a buzzard’s underwing as it turns, stalls and drops. I watch the kites hunt their own shadows over the tweedy, chaff-strewn ground, and almost miss the buzzard as it flies up with what is unmistakably – even at distance – a large grass snake, dangling like an upside-down question mark from its talons.