Ash trees are one of the most common trees found in our natural and built environment and can be found within parks, gardens and next to roadsides.
Ash Dieback Disease (ADD) is a highly destructive fungal disease of ash trees. Evidence suggests that at least 50% to 75% of Scotland’s 11 million mature ash trees may die over the next 20 years.
The disease is now widespread within the UK. At this moment in time there is no cure for the disease and in most instances leads to the irreversible decline of the ash tree.
Once first infected through the leaves or twigs, the speed at which a tree is overcome may vary with its age. Young trees can die within a couple of years and mature trees usually take longer. However large trees can become dangerous long before they die, so owners must take action to ensure safety, particularly if affected trees are near highways or footpaths. Ash trees at an advanced stage of infection will suffer from decay making them more prone to root, stem and/or branch failure.
Urgent action is needed by the owners of infected trees to ensure they don't become a danger to people or property.
What to look for
ADD is caused by a fungus and causes leaf loss and crown dieback. The symptoms are:
- Leaves develop dark patches in the summer.
- Leaves will then wilt and discolour to black and may shed early.
- Dieback of the shoots and leaves is visible in the summer.
- Lesions develop where branches meet the trunk and are often diamond-shaped and dark brown.
- Inner bark looks brownish grey under the lesions.
- New growth from previously dormant buds further down the trunk which is known as epicormic growth and is a common response to stress in trees.
More details about the disease can be found on the Woodland Trust's website.
If you have concerns regarding infected ash trees on council-owned land please report it:
What we are doing
We plan to commission an Ash Dieback Action Plan to guide the required work on a risk-based approach. In the meantime, survey work has begun on trees on council-owned land to assess the spread and impact of the disease.
New council-owned sites suitable for tree planting are being identified. While these sites may not be close to the locations seeing most loss, the additional trees will help improve our biodiversity and assist with carbon capture and alleviating the impacts of climate change.
We are developing a long-term operational plan to manage our woodlands, which will include compensating for the impact of the loss of trees through ADD and to increase and improve woodland cover.
Information for land owners
If you have an infected ash tree on your property or land, you should be aware of your responsibility to ensure it does not become a risk to other people or property.
Ash trees can decline rapidly once infected and become brittle and weak at the roots, especially if a secondary pathogen attacks the tree.
If your ash trees are not infected then they should not be felled. A small number of ash trees are resistant to the disease and others are able to tolerate infection and return to reasonable health. These trees will be valuable for the continuation of the species.
If the disease is identified you should follow the guidance set out in the national toolkit: Ash Dieback Toolkit for Scotland - The Tree Council
Further advice on your ash trees can be sought from a suitably qualified arboriculturist.
