The poet John Clare crossed here 180 years ago seeking the “furze and clouds” of Buckhurst Hill, but I’m happy to linger on Whitehall Plain amid its dazzling drifts of buttercups. Natural grasslands are now rare in southern England – 98% of them were destroyed in the 50 years after 1945 – and too often seen as easily replicated green space. Not here in Epping Forest, though. Beneath its surface gloss of buttercups, this old pasture, which straddles London’s boundary with Essex, is complex and dynamic.



As I crouch at buttercup level, the hum of hoverflies is intense and I’m peppered by soldier beetles, blundering about in the brilliance. Different plant communities interleave, vying for space. Ginger flower-heads of meadow foxtail dominate wetter clays, while on drier ground sweet vernal-grass, bents and fescues mingle. Yorkshire fog infiltrates nutrient-rich areas and common sorrel forms tall red swaths between chequered patches of common knapweed.

But a rarer plant has become the new orchestrator of these plant dynamics. After decades of absence, yellow rattle has recolonised Epping Forest, possibly via hay-cutting machinery. Rhinanthus minor’s own roots are weak, but they tap into those of grasses and clovers to steal their water and nutrients, suppressing their growth and altering the balance between species. This hemi-parasite is a botanical Robin Hood, releasing butterflies and their food-plants from the oppression of shade.

Yellow rattle and grass vetchling. Photograph: Jeremy Dagley

I can map this daylight robbery in the extensive patches of low turf, studded with yellow cinquefoils, tormentils and bird’s-foot trefoils across which common blue and small copper butterflies dance. And although some grasshoppers, like the meadow and common green, favour longer swards, bounding away from me on the short turf patterned with zig-zag clover are tiny nymphs of field and stripe-winged grasshoppers.

To appreciate the full diversity, though, requires heightened senses. For insects, the buttercups are a shimmering sea of ultraviolet signals. Homing in on them, metallic green Oedemera beetles plunder pollen, while eager red-tailed bumblebees follow invisible guidelines to lidded pools of hidden nectar. And as I head home, I cross a sward where field woodrush and red fescue create a cushioned turf so soft I want to kick off my shoes and tread barefoot.

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