Latest news on ash dieback and implication for Tees Valley woodlands

On 28 February Sue Antrobus and Martin Allen represented the Tees Valley Nature Partnership at a Forestry Commission Seminar on Chalara die-back of ash and other pests and diseases threatening woodlands in Yorkshire. The conference was attended by over 100 people, ranging from woodland owners and managers, foresters, landowners, conservationists and tree nursery managers. Presentations were made by research scientists from FERA (Food and Environment Research Agency) and Forestry Commission staff on current work on monitoring and mapping the spread of the Chalara, the threat it the disease, disease diagnosis, disease management and implications for grants and licence.

The Forestry Commission will be making the presentations available on their website shortly but in the meantime, the key points that Martin and I picked up were as follows;

  • Eradication of Chalara is not possible and it will spread of the disease to most parts of the UK is inevitable over time, with latest modelling by Cambridge University predicting that with 7/8 years coverage of all of the Uk apart from parts of Northern Scotland.
  • Saplings are more prone to die back with adult trees surviving several years and for these deaths is usually caused by a secondary infection such as honey fungus.
  • Levels of resistance and its genetic control are still unclear, with very different percentages of survival reported in different locations across Europe. It is believed that trees that lose their leaves early in autumn may be less susceptible.
  •  The government is taking a scientific evidence based approach to control measures. An interim control plan was published in December which is being updated, based on new surveys and research and is due to be published in March.

Interim Chalara Control plan
As part of the control plan newly planted diseased trees and diseased trees in nurseries will be traced and destroyed but mature trees will not currently be removed, as they are valuable to wildlife, take longer to die and can help us learn more about genetic strains that might be resistant to the disease.

The Forestry Commission website is the best place to visit for up to date information, videos on identification and bio security and information on reporting suspected cases

So what will be the implications for Tees Valley’s woodland and hedgerow trees?
Ash is a major component in many of our woodlands in the Tees Valley and in many of our ancient woodlands it forms stands with sycamore, with saplings of both species usually abundant in the scrub layer. The shorter term impact will be less ash regeneration and an increase in dead standing wood. Dead standing timber is an important wildlife habitat and is at present not common in our woodlands. Longer term it may be that as a result of loss of canopy of ash that these gaps will be exploited by sycamore.