Britain's ash trees face threat from emerald ash borer

After wiping out 10s of millions of ash trees in North America, the emerald ash borer is on its way to Britain.

Dr Stephen Woodward, a professor at the University of Aberdeen, has revealed the small green beetles have arrived in Moscow and will reach our shores in 15-20 years, if not sooner.

"There are plenty of ash trees in woodlands, hedgerows, parks and streets between Moscow and western Europe," said Dr Woodward. "In the absence of a very heavy sanitation cutting programme, there is nothing to stop the borer spreading here."

Despite not causing harm to the ash trees they co-evolved with in native Asia, the insects are deadly to other types of ash.

Their larvae eat the tissue supplying water and nutrients to the trees, starving and killing them within two or three years of infestation.

The borers are the second threat our ash trees have faced in recent years. Numbers of trees have been depleting since a deadly fungus called the dieback was introduced to the UK in 2012.

Dr Woodward believes the spread of the borers combined with the impact of fungus infestation will lead to total elimation of ash from the UK. He is calling for wood from ash borer infested zones to be stopped from entering the the EU to slow down the spread of the bugs.

"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," said the tree pathology specialist.

"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."

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