Large trees are important in terms of carbon storage - with large quantities of above ground biomass, lots of carbon is locked away for years. Trees like Sequoiadendron giganteum, the giant redwoods, are truly large trees;. They are, by volume, amongst the largest trees in the world and incredibly long lived.  Some are thought to be over 3000 years old.

Seeds of Sequoiadendron giganteum only arrived in the UK in the 1850’s, brought in by Patrick Matthew and William Lobb.  Lobb was employed by the Veitch Nurseries, based in Exeter.  He travelled extensively in both North and South America (including Argentina and Chile), and brought back not only seeds of the giant redwood but also some 3000 seeds of the monkey puzzle tree (Araucaria araucana).  He made a second trip to South America and brought back many different species of flower, including the chilean bellflower, the flame nasturtium, species of myrtle, and Escallonia macrantha.

Exotic trees and shrubs were much prized by wealthy Victorians, and redwoods were planted in the estates and at the entrances of many grand country properties.  They also make appearances in many public parks and gardens, see for example the redwoods at the Lower Pond at Whinfell Quarry Garden in Sheffield. Forestry England estimates that there are half a million Sequoias (giganteum & sempervirens) in the country, and nearly 5000 giganteum trees are recorded by location by redwoodworld.co.uk, the woodland trust ancient tree index and the Forestry Commission.  

Though it is only some 170 years since their introduction to the UK, some of these trees are amongst the largest trees in the country. This despite the fact that the climate here is not the same as that on the West Coast of America, their 'natural home'.  Due to their growth rate and carbon sequestration potential, there has been some discussion as to whether they might be included in commercial planting initiatives as they seem resilient to changes in climate, rainfall, soil moisture etc.  Disease resistance in another consideration. 

The growth and biomass of some 97 Sequoias at three different sites (Lakehurst, Havering and Benmore) has recently been investigated (using laser scanning)*.  The growth of the trees at Havering was less than that at the other sites, possibly due to lower rainfall (and increased competition) in the East.  However, the growth rates of the trees studied were in the region of 150kg above ground biomass per year (this equates to 81kg of carbon per year).  

Such growth is broadly similar to that of their American counterparts of a similar age.  It would seem that Sequoias might be a good choice for planting in terms of carbon uptake.

*Full details of this work here : https://royalsocietypublishing.org/doi/10.1098/rsos.230603