As our climate warms, the pressures on global forest ecosystems from extreme climate events are expected to increase across much of the world (Anderegg et al., 2020; Brodribb et al., 2020). Of particular concern is the increasing threat to tree health and productivity posed by drought. Despite a predominantly cool maritime climate, forest ecosystems in the UK are vulnerable to drought, as the effects of both the historic droughts of 1976 and 2003 (Cavin et al., 2013; Cavin and Jump, 2017) and the more recent drought of 2018/19 demonstrate, the latter extending across much of mainland Europe (Buras et al., 2020; Turner et al., 2021). Despite the pressing need to increase the overall resilience of natural and managed forests, remarkably little work has attempted to quantify the impact of historic drought events on forest growth in the UK. As a result, very little is known about the drought resilience of some of our most abundant and economically important tree species.
A recent series of Quarterly Journal of Forestry articles reviewed progress made by the UK forest sector so far, and the current state of resilience knowledge (Tew et al., 2021a, 2021b), including evidence of the historic impact, and future threat of extreme events on UK conifers (Spencer, 2018). In terms of the risks posed by drought, these articles largely drew on evidence from other countries and translated it to a UK setting. These knowledge gaps are particularly relevant for key conifer species such as Scots pine (Pinus sylvestris) and Sitka spruce (Picea sitchensis), which collectively make up over 68% of all coniferous forest area in the UK (Forest Research, 2020). This lack of UK-specific knowledge on how key UK tree species are likely to respond to drought hampers our ability to act to improve the resilience of UK forestry to our changing climate (Tew et al., 2021a). In this context, a research collaboration between the University of Stirling and Forest Research has been seeking to better understand drought impacts and resilience in planted UK forests using dendrochronological methods.