Researchers found that the Victorians brought so many seeds and saplings to Britain that the trees now outnumber those in their US homeland

Three redwoods tower over Wakehurst’s Elizabethan mansion like skyscrapers. Yet at 40 metres (131ft) high, these are almost saplings – not even 150 years old and already almost twice as high as Cleopatra’s Needle.

“At the moment they’re some of the tallest trees in the UK and they are starting to poke above the forest canopy. But if they grow to their full potential, they’re going to be three times taller than most trees,” says Dr Phil Wilkes, part of the research team at Wakehurst, in West Sussex, an outpost of Kew Gardens. One or two of these California imports would be curiosities, such as the 100-metre high redwood that was stripped of its bark in 1854 and exhibited to Victorian crowds at the Crystal Palace in south-east London, until it was destroyed by fire in 1866.