Planting groves of sequoias to offset our lifetime carbon footprints

One of the things that fascinates me about the times in which we live is the stories of people who find that their individual actions resonate with others, and thus lead to a much bigger story that involves many more people.

So is the story of Henry Emson, a resident of the United Kingdom, who planted two California Sequoia seedlings for his young children as a way to compensate for the carbon footprints of their lives. As people heard about it, they wanted to join in.

“The genesis of the idea for One Life One Tree was planting Giant Sequoias for my two young children, starting their journey to a carbon neutral life as early as possible – a single Giant Sequoia tree captures the same amount of CO2 as your average UK person’s total emissions during their lifetime (around 520 tonnes),” Henry told an interviewer.

By m01229 from USA – Giant Sequoias, CC BY-SA 2.0,

“Concerned about the global climate crisis and the scale of the action needed, I began offering to plant Sequoia trees for others who wanted to join us on this journey. The response was amazing so I started buying more land, brought expert forestry contractors in, and we now have almost 1,000 Sequoia Patrons.”

Now One Life One Tree aims to plant 100,000 Giant Sequoias, creating The Great Reserve, because things have changed since 2019 when the project began. Today, in the USA, Giant Sequoias face a new ‘triple threat’ from drought, increased heat, and super-heated inferno fires. Already on the IUCN Endangered Species Red List, there are only an estimated 75,000 old growth Sequoias left. So the idea behind the Great Reserve is to “replicate the stock of surviving Sequoias in the US by planting and nurturing 100,000 Giant Sequoias here in the UK as an effort of ‘assisted migration’ to offer a more secure future for the species.”

But that doesn’t mean there will be one great forest of sequoias, because the trees are planted in groves, along with native trees, in various parts of the UK, mostly in felled forests in hard-to-reach hillside or mountain locations. So far, there are groves in Hampshire, Buckinghamshire, and Brecon, with the current site near Abergavenny in Wales. Future possible locations include Devon, the Lake District, and Scotland.

Sequoias aren’t new to the UK, as it happens. In Victorian times, people brought seeds to England and planted them on family estates. People often ignored the fact that Sequoias grow in community, roots reaching out to others of their kind. They were lonely, and their growing conditions weren’t optimal; nonetheless, many grew to be magnificent trees, Emson says

By Tuxyso / Wikimedia Commons, CC BY-SA 3.0,

But because Sequoias capture more and more carbon as they age, the conditions in which they grow matter – a lot.

“For the Sequoia, the amount of carbon it captures is an incrementally increasing upward moving curve.  The older it gets, the greater the circumference of the tree and height, thus the greater the carbon mass it lays on each year with a fresh growth ring.  To give context in year 10 the Sequoia adds 0.02 tonnes (2kgs), in year 50 it adds 0.5 tonnes, in year 100 it adds 1.2 tonnes, in year 250 it adds over 3 tonnes.”

Although the sequoias in the UK are about 150 years old, in terms of sequoia life spans they are effectively only teenagers. And that affects how much carbon they will offset, which in turn affects the answer to the question that Emson is often asked – How long does it take for a Giant Sequoia to capture the average UK citizen’s lifetime carbon footprint?

In 2017, the World Bank said that footprint was about 6.5 tonnes a year. “If you take the average life expectancy in the UK of 80 years old, that equates to 520 tonnes of CO2 over a lifetime,” he says, though it varies over our lifetimes – fairly small as babies, and less in old age as we become less active.

“We buy land in regions which are optimal for Sequoia trees to grow and plant saplings for each of our ‘Sequoia Patrons’,” he says. “We then nurture the saplings to a size where protection from wildlife is no longer needed, and commit to donate the land to a tree friendly charity. We also plant native species on the site which are left to mature alongside our Sequoias to help with biodiversity and prevent monoculture.”

When they grow in these kinds of conditions, sequoias will grow fast and strong, he says, especially in comparison with the others who didn’t have favourable conditions to start with.

By LGalcan – Own work, CC BY-SA 4.0,

“Our calculations for Sequoia growth rate are based on existing Sequoias in the UK, where growth rings average out at 1.15cm, and a height increase of 1.5ft per annum.  From that we can forecast the volume of the tree as it grows year on year, until we reach our target 500 tonnes.”

But given that sequoias grow slowly, Emson’s group plants three native trees for each sequoia to increase the CO2 uptake, and each grove is overseen by forestry experts and protected from browsing wildlife.

Who buys the trees, he was asked. This was his answer:

“They tend to be environmentally-minded, of all ages and creeds, the binding factor being the desire to take action. People chose to become a tree patron for many reasons, from parents planting a tree for a new baby or a grandad wanting to give something back, having lived a full life. More recently we’ve seen families choosing to plant a Giant Sequoia as a lasting and sustainable memorial to a loved one. Our patrons want to create a bond with their tree, and the person it’s been planted for, and to watch it grow for generations to come.

“We encourage our patrons to come along to one of our Planting Days so they can create a sense of ceremony when planting their tree. They can roll up their sleeves, get involved and take photos of the event. A Giant Sequoia is a legacy – a monument to your loved one which can live for thousands of years – as well as providing a net zero carbon footprint for their life.”

Knowing that Sequoias grow for as long as 3,000 years, Emson says, “it is a slightly surreal feeling planting a tree that will be standing further into the future than the Roman Empire is to us now in the past!”

In the USA, Archangel Ancient Tree Archives has been working for a quarter century to protect forests and old growth trees, and has learned to clone ancient trees – something scientists did not think was possible. David Milarch says that the era of preservation is past; now is the era of restoration, and we need to adjust our thinking accordingly, especially as climate change worsens.

Archangel has created “living archives” in many areas of the world, including Michigan, and partnered with trust properties to accept its trees, “ensuring that the hard work expended to capture these tree genetics will live on for generations to come.” But there is still a lot to do, it says. It is planting Giant Sequoias in Ireland, New Zealand, and Australia, among other places, because the US west coast is warming so quickly.

“With over eight thousand tree species on the endangered species list and our world in such ecological peril, we cannot rest until we are able to plant tens of millions of these important trees globally.”


One Life, One Tree website.

The Great Reserve – 100,000 Giant Sequoias to protect the future of the species. One Life, One Tree. Feb. 14, 2022

A Day in the Life of… Henry Emson, Founder of One Life One Tree. Angel and Dove, Jul. 11, 2021

Henry Emson interviews David Milarch from the Archangel Ancient Tree Archive. YouTube, Oct. 23, 2020

Archangel Ancient Tree Archive website.


In burned-out groves of giant sequoias, crews plant seeds of hope. Will they survive? Los Angeles Times, Jun. 11, 2023