Survey of ash trees in Devon churchyards to monitor spread of disease
A SURVEY of ash trees to monitor the level of the disease Ash Dieback in churchyards is underway in Devon.
The Devon Living Churchyards Project is asking people to send them details of ash trees in their churchyards.
They would like survey participants to email details of:
- Church name and address/postcode
- How many ash trees above 75mm in diameter? Please measure the girth of each tree at chest height.
- How many young ash trees below 75mm in diameter
- What percentage of leaf cover is healthy
- Surveyor’s name
- Survey date
Please email findings to David Curry: firstname.lastname@example.org
Ash trees are increasingly affected by Ash Dieback, a disease caused by a fungus (Hymenoscyphus fraxineus). The disease causes leaf loss and crown die back in affected trees, and it can lead to tree death.
It is clear from the European experience of the disease that a significant number of ash trees could be lost from Devon over the course of perhaps the next 10 – 15 years – up to ten times the number of elm trees affected by Dutch Elm disease.
In the long term trees cannot recover from infection, but larger trees can survive infection for a considerable time and some might have genetic resistance and not die.In the short term spreading can be delayed by the removal and burning of fallen leaves during the autumn months and the removal and burning of ash seedlings using secateurs or loppers.
Martyn Goss, the Diocese of Exeter’s environmental officer, said: “One of the really sad features of our time of living on a desecrated planet is the increasing loss of animal and plant species, and Ash Dieback is the latest of a number of diseases now likely to decimate Devon’s mature tree population.”
Symptoms of Ash Dieback include:
- On leaves: Black blotches appear, often at the leaf base and midrib. Affected leaves wilt
- On stems: Small diamond-shaped lesions appear on the bark of stems and branches and enlarge to form perennial cankers. The infection may girdle the stem and kill it in a single season. If the bark is peeled, the wood underneath has a brownish to grey discolouration. This discolouration extends beyond the bark necrosis. However, recent reports from colleagues in Norfolk and Suffolk have pointed out that now trees are just showing signs of dieback and not showing classic diamond lesions.
- On whole tree: Affected trees show extensive dieback of shoot, twig and branches.
The following websites are helpful in identifying likely symptoms of the disease: