Having recently contended with the deadly dieback fungus, the UK’s ash trees face a fresh threat from the Emerald Ash Borer.
The small green beetles have wiped out tens of millions of ash trees in North America and are now making their way to British shores.
Now experts are calling for a ban on ash wood movement in infected zones, to stop the spread of the bugs.
The creatures have already been found in Moscow and it is predicted that trees here could be under threat within the next 15-20 years.
Dr Stephen Woodward, a professor at the University of Aberdeen, said: “There are plenty of ash trees in woodlands, hedgerows, parks and streets between Moscow and western Europe.
"In the absence of a very heavy sanitation cutting programme, there is nothing to stop the borer spreading here.”
Back in their native Far East, the borer beetles cause no harm to indigenous Asian ash trees, yet they will kill others.
Once the trees become infested, they can be dead within two or three years. The bug’s larvae eat the tissue supplying the plants with their water and nutrients, effectively starving the tree to death.
Dr Woodward, a tree pathology specialist, believes that this latest foe could cause the total extinction of ash trees in the UK.
He says: “It is quite likely that ash trees that show tolerance to the ash dieback pathogen will not have any ability to resist attack by the emerald ash borer."
"Strict measures will need to be in place at EU borders to prevent the borer entering the European Union. Movement of any ash wood, even twigs, should be banned completely."