We are all aware of the encroaching Ash die back disease (Chalara fraxinea), threatening so many Wiltshire trees, but we may not recognise the signs. Here is some helpful information from the Forestry Commission about how to identify the signs, and reduce the chances of inadvertently spreading the disease.
More information about the disease and how it is spreading
For further information, you can go to the following websites:
Forestry Commission https://www.gov.uk/government/organisations/forestry-commission
Woodland Trust Pests and Diseases