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Chalara dieback of ash

Chalara dieback of ash is a serious disease of ash trees caused by a fungus called Hynenoscyphus fraxineus). The disease causes leaf loss and crown dieback in affected trees, and it can lead to tree death.

Further information on Chalara
We are treating the Hynenoscyphus fraxineus fungus as a  ‘quarantine’ plant pathogen, which means that we can take legally enforceable action to contain or eradicate the fungus when it is found.

We have sent out letters to our customers whose trees or woodlands may be at risk, a copy of the letter and further information are available on this web page.

Chalara dieback of ash - Reports
We are very grateful for your report (as a response to our letter or otherwise). We are working through the backlog of reports we have and are sorry that we may not be able to respond to each report individually but every one of them will assessed and for each report we will:

  • decide it isn’t Chalara die back of ash; or
  • ask for more information which may include requesting photographs or more detail; or
  • arrange for someone to do a further investigation onsite

The disease does not spread via spores from the fungus during the winter so we have the time to carefully examine each report. It is our priority to destroy recently planted trees but mature trees with the disease do not need to be felled.

Last updated: 15th February 2017