Killer ash tree disease which took root in Norfolk could cost the UK £15bn, says study

A deadly disease killing the country's ash trees could cost the British economy almost £15bn, a study has warned – with taxpayers picking up much of the bill.

A tree infected by ash dieback at Lower Wood, Ashwellthorpe. Picture: Dr Anne Edwards/John Innes Centre - Credit: Dr Anne Edwards/John Innes Centr

Norfolk became the epicentre of the UK ash dieback outbreak in September 2012 when the first confirmed case of the infection in wild trees was found at Lower Wood in Ashwellthorpe, near Wymondham. The discovery triggered a scientific fightback led by the John Innes Centre in Norwich.

The disease originated in Asia and is thought to have been brought on imported trees to the UK, where it is believed it could kill up to 99pc of our native ash trees.

Experts calculating the economic impact of ash dieback said they were 'shocked' at the magnitude of the total cost to society, which they estimate at £14.8bn over 100 years, with half of those costs (£7.6bn) falling within the next decade.

The biggest cost will be from the loss of benefits that woods and trees provide, such as clean air and water and storing carbon dioxide, the study published in the journal Current Biology found.

Fruiting bodies of the ash dieback fungus on leaf-stalks in Lower Wood, Ashwellthorpe, Norfolk. Picture: Elizabeth Orton. - Credit: © Elizabeth Orton

Clean-up costs – such as felling dangerous trees on roadsides, railway lines and in towns and cities – will cost around £4.8bn, with much of that burden falling on local councils, said researchers from the University of Oxford, Fera Science, Sylva Foundation and the Woodland Trust.

Dr Nick Atkinson, senior conservation advisor for the Woodland Trust and co-author of the paper, said: 'When ash dieback first entered the country, no one could have fully predicted the devastating impact it would have on our native habitats.

'To see how this has also affected our economy speaks volumes for how important tree health is, and that it needs to be taken very seriously.'

The study says ash dieback will eventually cost a third more than the Foot and Mouth disease outbreak in 2001, which plunged livestock farms into their worst crisis for decade.

The researchers called for a nationwide replanting scheme which could reduce the overall cost of ash dieback by £2.5bn by ensuring that lost benefits are replaced.

And much tighter biosecurity controls are needed on imports of live plants to prevent further pests and diseases entering the UK, said Dr Atkinson.

'We need to learn from past mistakes and make sure our countryside avoids yet another blow,' he added.

A Defra spokesman said: 'Since ash dieback was identified in 2012, we have invested more than £6m in ash dieback research and £4.5m to strengthen border security. We currently have some of the strongest import controls in Europe.'

The spokesman said the government was funding research to make ash trees resistant to the disease, supporting replanting with other tree species, and helping local authorities manage ash dieback infections.