Ash dieback: How the British landscape is changing
12 June 2013 Last updated at 06:57 BST
The Forestry Commission is warning that a whole generation of ash trees is likely to die because of the unstoppable spread of the ash dieback disease.
It has been a year since it was first discovered in the UK and now the trees are in leaf, the full impact of the disease is starting to become evident.
Jeremy Cooke reports.