Almost all the ash trees in the UK and across Europe are likely to be wiped out by a “double whammy” of a bright green borer beetle and the fungus that causes ash dieback, according to a comprehensive new academic analysis.
The loss of the ash, one of the most abundant tree species in the UK, would mean losing even more trees than the 15 million elms killed by Dutch elm disease in the 1970s. Ash is the most common hedgerow tree, with 60,000 miles of tree lines. It is the second most common tree in woodland, after the oak, and there are many ash trees in towns and cities.
“Between ash dieback and the emerald ash borer, it is likely that almost all ash trees in Europe will be wiped out, just as the elm was largely eliminated by Dutch elm disease,” said Peter Thomas, a tree ecologist at Keele University, UK, who did the analysis, published on Wednesday, in the Journal of Ecology. “The two together are a double whammy.”
Thomas said the arrival of the emerald ash borer, originally from Asia but which has devastated North American ash and is now as close as Sweden, is inevitable: “It is only a matter of time before it spreads across the rest of the Europe – including Britain. Our European ash is very susceptible to the beetle and the beetle is set to become the biggest threat faced by ash in Europe – potentially far more serious than ash dieback.”