A research paper has been published which estimates that  ash dieback is set to cost the UK £15 billion and is expected to kill 95-99% of ash trees in Britain.

A team of researchers from Fera Science, University of Oxford, Sylva Foundation and the Woodland Trusts have calculated the economic cost and impact of ash dieback and the predictions are astounding:

• Ash dieback is estimated to cost Britain £15 billion with £7 billion being over the next 10 years
• The total cost is 50 times larger than the annual value of trade in live plants to and from Britain, which is the most important route by which invasive plant diseases enter the country
• There are 47 additional known tree pests and diseases that could arrive in Britain and cost a further £1 billion or more worth of damage

Dr Louise Hill, researcher at Plant Sciences at the University of Oxford and lead author of the study, said:

    ‘The numbers of invasive tree pests and diseases are increasing rapidly, and this is mostly driven by human activities, such as trade in live plants and climate change. Nobody has estimated the total cost of a tree disease before, and we were quite shocked at the magnitude of the cost to society. We estimate the total may be £15 billion – that’s a third more than the reported cost of the foot-and-mouth disease outbreak in 2001. The consequences of tree diseases for people really haven’t been fully appreciated before now.’

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. It is clear that to avoid further economic and ecological impacts, we need to invest more in plant biosecurity measures. This includes better detection, interception and prevention of other pests and diseases entering the country. We need to learn from past mistakes and make sure our countryside avoids yet another blow.’

Millions of ash trees line the roads and urban areas of Britain and the predicted costs arise from clearing up dead and dying trees and the benefits that will be lost from the trees, for example; water, air purification and carbon sequestration.

The cost also takes into account lost profits for forestry and plant nurseries, as well as the price of surveying affected trees and replanting hedgerows.

Scientists say that the total cost could be reduced by replanting lost ash trees with other native trees, but curing or halting the disease is not possible.

Recommendations:

• A nationwide replanting scheme to ensure that lost ecosystem services are replace, which could reduce the overall cost by £2.5 billion
• Investment in biosecurity and sourcing of safe plant material is essential to further economic and ecological impacts
• Introduce tighter controls on imports of all live plants for planting, as this is the largest pathway through which tree diseases are introduce

Read the full paper here: www.cell.com/current-biology/fulltext/S0960-9822(19)30331-8

What is Ash Dieback?

Ash dieback, also known as Chalara dieback of ash, is a disease killing ash trees across Europe. It blocks the water transport systems in ash trees causing leaf loss, lesions in the woods and bark, and ultimately the dieback of the crown of the tree. Originally from Asia, it was first found in Britain in 2012 and is thought to have been brought to the UK years earlier on infected imported ash trees.