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An ancient ash in Hodgehill wood


The landscape of the Yorkshire Dales National Park is characterised by important ancient semi-natural ash woodlands. These woodlands also contain rare and endangered plants and insects. At the moment ash trees are threatened by a disease called Chalara ash dieback which has been found in the wild in East Anglia and in recently planted new native woodlands.

Ash Tree – Fraxinus – Family: Oleaceae
Credit: Geoff Garrett YDNPA

Chalara ash dieback is a serious disease of ash trees which is caused by a fungus called Chalara fraxinea (C. fraxinea). The disease causes leaf loss and crown dieback in affected trees, and it can lead to tree death. Ash woodlands contain a number of tree species including ash, rowan, hazel, hawthorn and holly. The Yorkshire Dales National Park Authority (YDNPA) considers that the ash woods are a priority habitat and will continue to do so. We will monitor the progress of the disease and will endeavour to ensure that these habitats continue to be safeguarded.

Ash dieback
Ash dieback

Further information on Ash Dieback can be found within the trees and woodland pages of the YDNPA website.