Rossendale Borough Council

Ash Dieback Disease



The ash dieback disease is caused by the fungus "Chalara Fraxinea". Ash trees are common within Rossendale and they are found in parks, private gardens, along our roadsides and in the wider environment. Currently there are no confirmed infected trees within the borough.

  • Ash trees belong to a group of trees with the Latin name "Fraxinus" and the fungus will only infect trees in this group. The most frequently affected type is Fraxinus excelsior, which is our native or common ash tree. Other types of ash trees can also be affected by the disease directly or by being a host to the disease. Fraxinus angustifolia, commonly known as the narrow leaved ash and forms such as weeping ash trees are also considered particularly at risk.

There is another common tree called Mountain Ash, which is also known as Rowan. This tree belongs to a group of trees with the Latin name "Sorbus" and despite its common name is not an ash tree. Mountain ash is not at risk from the ash dieback disease.

Our ash trees are now dormant for winter and have lost their leaves making identification of the disease extremely difficult until next spring.

The government is working closely with other organisations to identify the extent of the disease and provide guidance on any necessary action.

There is a lot of useful information on the internet to help identify ash trees and recognise the symptoms of ash dieback. Websites of the Forestry Commission, Department for Rural Affairs (DEFRA) and Woodland Trust are all very helpful.

If you think you have spotted the disease, please check the symptoms video and guide at and provide details on the Tree Alert form you will find there.