Ash dieback Questions & Answers
November 7, 2012
You’ve probably heard in the national news about ash dieback disease which has recently been discovered in the UK. We asked Robin Ridley, a member of the South Yorkshire Forest Partnership team about what affect this disease could have in South Yorkshire:
‘Ash is an abundant tree in our landscape. The loss of these trees, if that happens, will have a profound effect on the environment; not just our our woodlands, also our streets and gardens too. Hopefully we will not have a headlong rush in cutting down and destroying infected trees as with Dutch Elm disease – which did not solve the problem. We also need to see where there are resistant varieties of Ash, which we can start to breed from to replace the susceptible varieties.’
Ash dieback Q&As
What is ash die back?
Ash dieback (latin name- Chalara Fraxinea) is an invasive pathogen or fungus which is thought may have originated in the Far East although non-destructive variants of the fungus were first identified in Europe as far back as 1851.
It was first reported in its destructive form in Poland around 1992 and has steadily spread across much of mainland Europe. Over the past decade it has been responsible for the reported deaths of around 90% of Ash trees in Denmark.
The fungus was first found in Britain in February 2012 in young Ash nursery stock imported from the Netherlands.
It was first discovered in the wild during October 2012, in the East of England.
As of 7/11/12 there were 115 sightings, 15 nurseries, 39 planting sites and 61 locations in the wider environment.
These numbers will increase as it is believed that wind blown spores and infection may have been active for a number of years prior to its detection.
In South Yorkshire there has been confirmation of infestation at a planting site as well as reports of possible sightings via the Smartphone/Crowd Sourcing App:
How many of our trees are Ash?
Nationally around 30% of trees in the environment are Ash, some estimates put this at around 80 million trees. It is therefore a significant feature of our landscape.
What happens to infected trees?
Initially there are small spots of necrotic (or dead cells) on stems and branches, these enlarge and form lesions which result in wilting and then dieback of branches.
The disease causes leaf loss and crown dieback in affected trees, and it can lead to tree death. Younger trees would succumb to death more quickly than older trees which may take years to die. If you want to check an Ash tree for symptoms visit the Forestry Commission’s symptom checker.
How is the disease spread?
It is believed that the fungal spores and hence disease is transmitted mainly through the air blown over from Northern Europe. However, the disease was first noticed in the UK via infected imported trees from Europe.
What is being done in response?
The Forestry Commission and the Food and Environment Research Agency (FERA) carried out a national survey in early Nov 2012 to assess how widespread the disease is. The findings will be issued soon.
The Government have stated that 100,000 infected trees (mostly nursery stock) have been destroyed to minimise the risk of the disease spreading.
However given the experience of the steady spread across mainland Europe and the airborne nature of the cause of disease, it is unlikely that there are any effective preventive measures that can be employed to stop its spread.
Has it been found in South Yorkshire?
It has been confirmed in at least one new planting site and there are a few other un-confirmed reports of possible cases. Please see the Forestry Commission website for a distribution map for the latest position.
What has South Yorkshire Forest Partnership being doing to tackle this issue?
We have been working with the Forestry Commission on the National Rapid Survey that took place in the first week of November 2012 to try and help identify the disease’s reach so far.
We are offering information and help to woodland owners and will endeavour to keep them informed as news and research emerges.
Also, to prevent the spread of the disease, we will be planting no ash trees at this year’s Gift That Grows tree planting events. Our role will be to get the word out to people in South Yorkshire about the guidance available and any proposed controls.
What happens next?
Following the national survey, the Forestry Commission will publish information on how far the disease has spread.
Expert panels are due to meet to discuss ways of dealing with or mitigating against the disease.
Use Ashtag Smartphone App and tool to help track and report the disease.
For further information about Ash dieback or to report possible sightings contact the Forestry Commission:
Chalara helpline: 08459 33 55 77 (open 8am – 6pm every day) email@example.com
If you would like to discuss any concerns about local sites, please contact South Yorkshire Forest Partnership on 0114 2571 199 or email firstname.lastname@example.org