BE TREE-WISE TO ASH DIEBACK; As ash dieback continues to threaten the future of Britain's ash trees, HANNAH STEPHENSON examines the problem and offers a guide showing gardeners what to look out for in their own trees GARDENING.
ASH dieback was the big environmental story of 2012 - and the deadly fungus Chalara fraxinea threatening to blight our ash and so change the face of our countryside is not about to drift away in 2013.
In December, government figures revealed that the number of infected sites had more than doubled to 291 compared with the previous month.
More than half are mature woodland areas which were most likely infected by spores blown from continental Europe or Norway in the wind, rather than by diseased young trees imported from abroad, experts said. But how can you tell if the ash in your own garden is infected? What is the situation in the UK? The fungus was unknown in Britain until early last year. The first case was confirmed in ash plants in a nursery in Buckinghamshire, in a consignment which had been imported from The Netherlands. Since then, more infected plants have been confirmed in nurseries in a wide range of locations in England and Scotland. Experience on the continent indicates that it kills young ash trees very quickly, while older trees tend to resist it for some time until prolonged exposure causes them to succumb.
What are the symptoms? Dead or dying tops of trees, most easily seen throughout summer; wilting leaves, most visible in spring and early summer; lesions and cankers on stems/branches/shoots, visible throughout the year; dieback of leaves with brown/black leaf stalks, seen throughout summer; fruiting bodies on fallen blacked leaf stalks, visible June to October; staining of wood under bark lesions, visible throughout the year. Check your trees as they emerge into leaf.
What can I do if I think my tree has ash dieback? Fill out the Forestry Commission's 'Tree Alert' form on its website www.forestry.gov.uk or call the Chalara helpline on 08459 335 577.