El Niño-fueled winds threaten England's drought-stressed trees, experts warn

Kevin Martin, head of tree collections at Kew Gardens, explained that the extreme conditions have prevented trees from growing normally, making them less flexible and more brittle. He expressed concern that predicted strong winds from El Niño could have significant impacts. The UK's Met Office anticipates that the current El Niño event, potentially the strongest in over a century, will bring increased rainfall and storms to the UK this autumn.

Martin also highlighted the risk of root death, where dry spells followed by heavy rain can destabilize soil, potentially causing trees to fail at the root plate. He fears that species such as silver birch, common beech, and oak could be lost from landscapes where they are currently common. Ancient oak trees are particularly vulnerable, with experts noting their decline due to the hot and dry weather. The spring heatwave, which saw temperatures reach 35C, marked the hottest May on record and contributed to an unprecedentedly stressful growing season.

Simon Richmond, a technical officer at the Arboricultural Association, noted that while trees are resilient to single years of extreme weather, the likelihood of prolonged patterns due to climate change presents a significant danger. Following the 2022 heatwave, Kew Gardens lost over 400 trees. Martin predicts that the impact of this year's extreme weather could be far worse, with a significant amount of mortality expected at Kew and across the south-east, as many trees that survived 2022 may not withstand the current conditions. However, the full extent of this year's extreme weather's impact will likely not be known for another two to three years.

Marcus Lindner, a principal scientist at the European Forest Institute, cautioned that several years of extreme weather could push many tree species to their limits, with almost all species at risk. He explained that even drought-tolerant species have limits to repeated and continuous drought stress.