World’s largest trees to find their home in Britain as ‘peaceful giants’ rapidly die out in US

It is a Californian colossus which hails from the Sierra Nevada mountains.

But soon, the largest tree on the planet, which can be 300 feet (91.4 metres) high and have a circumference of up to 100 feet (34.4 metres), could be much closer to hand - in the Brecon Beacons.

While giant sequoias are rapidly growing in number in the UK as Britons plant the trees to offset their carbon emissions, numbers in America are rapidly declining due to climate change and forest mismanagement.

Extreme climate conditions mean that giant sequoias are registered as an endangered species by the International Union for Conservation of Nature, with around 80,000 left in North America today - down by around 98 per cent from peak levels two centuries ago.

Numbers are falling at a rate of around 10 per cent per year, with up to 14 per cent of mature sequoias lost in the Castle Fire of 2020 alone. While moderate fire is beneficial for sequoia reproduction, intense fires are devastating for the species.

The recent droughts in California are also an issue for the trees, which can require hundreds of gallons of water a day in summer periods.

Preservation organisations across the world are collaborating to find a place for the species to survive long-term. They believe that western areas of the UK might be a good fit, due to high levels of rainfall and moderate temperatures.

Campaigners say that without forest fire they will not be able to reproduce naturally and become an invasive species, and are instead each propagated and planted individually.

A company called One Life One Tree has already planted over 700 sequoias in the UK. There are plans to reach 100,000 by 2030, with sites in Buckinghamshire, Hampshire and around the Brecon Beacons. They call the project “The Great Reserve”, to maintain numbers of the trees for generations to come.

Each sequoia is planted with three native British trees to maintain biodiversity in the groves. The company charges patrons £395 to plant a sequoia, with the promise that it will help to offset their carbon emissions.

The company claims that a hectare of their sequoia groves could sequester 6,000 tonnes of carbon dioxide from the atmosphere over 100 years, which could be 10 times more than typical woodland due to the sequoias’ great height.

“The climate in the UK is very good for them,” said Henry Emson, founder of One Life One Tree. “We haven’t had one failure, they’ve all taken off. Sequoias are peaceful giants … They have been here for 160 or more years already and they are not a problem with native species."

David Milarch, co-founder of Archangel Ancient Tree Archive, an American charity which propagates trees that are in danger of extinction, said the disappearance of sequoias is “a devastation that we've never experienced before”. He added: “Henry is on the right track. The future will be in other countries, it’s already too late for California.”

The first sequoias were introduced to England in the mid-19th century by plant collector William Lobb, who produced saplings from some of the tallest trees in California and sold them to wealthy landowners. Lobb also popularised the monkey puzzle tree in the UK.

In the UK, the trees are sometimes called Wellingtonia, after Arthur Wellesley, the 1st Duke of Wellington, who had died just before the sequoia received its species classification.

However, anyone planning a trip to Wales to see the enormous trees might have to wait a few years. Although they grow rapidly, by about four feet a year, giant sequoias can take hundreds of years to reach their full height.

The trees are known for their hardiness and ability to withstand temperatures as low as -25F (-31C), as well as survive moderate forest fire.