Giant sequoia (Sequoiadendron giganteum) in the UK: carbon storage potential and growth rates.

Giant sequoias ( ) are some of the UK’s largest trees, despite only being introduced in the mid-nineteenth century. There are an estimated half a million giant sequoias and closely related coastal redwoods ( ) in the UK. Given the recent interest in planting more trees, partly due to their carbon sequestration potential and also their undoubted public appeal, an understanding of their growth capability is important. However, little is known about their growth and carbon uptake under UK conditions. Here, we focus on . and use three-dimensional terrestrial laser scanning to perform detailed structural measurements of 97 individuals at three sites covering a range of different conditions, to estimate aboveground biomass (AGB) and annual biomass accumulation rates. We show that UK-grown can sequester carbon at a rate of 85 kg yr , varying with climate, management and age. We develop new UK-specific allometric models for that fit the observed AGB with > 0.93 and bias < 2% and can be used to estimate biomass more generally. This study provides the first estimate of the growth and carbon sequestration of UK open-grown and provides a baseline for estimating their longer-term carbon sequestration capacity.