Among a canvas of copper, red and purple autumn leaves on display at Wisley garden in Surrey , south-east England, one tree stands conspicuously naked.

“The birch has lost all its leaves,” says Guy Barter, the chief horticulturist at the Royal Horticultural Society. “That’s the effect of drought, so it’ll have no autumn colour this year.”

Where a burst of sunny yellow foliage would normally brighten the display, the birch can offer only its ivory-white bark. After the hottest summer on record , the tree has dropped its canopy early, stressed from months of high temperatures and choosing to not lose any more water through its leaves.

This is also known as a “false autumn”, where the stress of extreme summer conditions prompts trees and plants to behave as if the season has changed.

Guy Barter, the chief horticulturalist at the RHS, at Wisley garden. Photograph: Martin Godwin/The Guardian

The birch illustrates how extreme weather driven by the climate crisis is reshaping the flow of the UK’s seasons.…