Ash Dieback has spread across the country and is now turning up in hedgerows not associated with infected plantations. The disease is caused by the fungal pathogen hymenoscyphus fraxineus (formerly chalara fraxinea), and is fatal to most ash trees with just a tiny survival rate for infected plants.
The disease is thought to have been introduced through imported nursery plants but it has spread widely since. Minister for Agriculture Michael Creed recently said: “over half the recent findings in forest plantations are in ash trees of native Irish origin”.
The Department has been running a Reconstitution Scheme since March 2013 under which €2.6 million has been paid to forestry owners whose plantations had to be ripped out and replaced as a result of ash dieback. Over 733ha of land have been replanted under the scheme, a figure which is expected to increase with the disease's spread.
Attempts to eradicate ash dieback in Britain have failed, so authorities there have resorted to issuing advice to members of the public who spot the disease. Meanwhile, a project to identify potentially resistant strains of ash is leading to some promising outcomes. The Nornex project brings together international experts in genetics and genomics from numerous laboratories and institutes. It aims to identify the genetic traits of tolerant plants and expand our information about their molecular structure, giving a better idea of what options are open with regard to breeding trees that can survive dieback in the future.
Alan Downie is coordinator of the project: "One of the absolutely critical parts of this was our international collaboration with people in Denmark. They had trees that they had already identified as being tolerant to the disease and we were able to apply our great strengths in genetics and genomics to that population."
Teagasc is also half-way through a four-year research project in conjunction with academics in London, France and Lithuania. This project has similar aims, using Asiatic ash varieties that are known to have innate resistance to the disease.
If you identify any ash trees infected by dieback, you can check the Department guidelines here. The Department wishes to be informed of any outbreaks by e-mail: email@example.com or by phoning 01-607 2651.