Ash dieback (Hymenoscyphus fraxineus)

What is Ash dieback?

Ash dieback, caused by the non-native fungus Hymenoscyphus fraxineus (formerly known as Chalara fraxinea), presents a significant threat to the UK's treescape on a scale not seen since Dutch Elm disease in the 1970s.

Ash is the third most common native tree in the UK, occurring in woodlands and other landscape settings, it has a high ecological value, cultural and historical significance within the county. Ash dieback is now found throughout the UK, eradication of the disease is not possible as this pathogen is an airborne fungus and is now considered endemic within the UK.

Information video on the signs and symptoms of Ash dieback and how we are dealing with the problem.

Latest updates

Notice of Ash dieback works on Surrey's Countryside Estate and the Downs Link route

In the interest of public safety, felling of diseased and dying ash trees is planned to take place in higher and medium risk areas around the county starting in the autumn, following the conclusion of ground nesting bird season. On the Countryside Estate, works are anticipated to focus around targeted areas of Sheepleas (West Horsley), Newlands Corner (near Guildford), Park Ham (near Bletchingley), Norbury Park (Leatherhead/Dorking), and Brockham Quarry. Some works will also be required along Beech Avenue (Effingham) to address Ash dieback and support proactive land management of the avenue.

Necessary works will also take place on Surrey County Council landholdings around the county with posters displayed in public locations to inform of upcoming works.

Planned works are subject to obtaining appropriate licenses, satisfactory survey results and other permissions as required, so locations may be subject to change. Felling licenses will be made available to view as they are received on the Ash dieback felling licences web page.

Due to the time required to liaise with partners and external agencies, and due to other external variables such as weather conditions and contractor availability, it is not possible to give start dates at the current time. Updates will continue to be posted on this page and on our Explore Surrey social media channels as they become available.

Areas of the Downs Link path are also affected by Ash dieback and are likely to require closures at times during the autumn and winter to facilitate felling works, which will affect public access. This is likely to apply on a stretch of the Downs Link south of Bramley to the north of Cranleigh. On-site notices will advise on work that is taking place and for approximately how long, with updates also posted online. Find out more about the Downs Link.

Public Engagement

Following our 'show and tell' site walks which took place in September, we also organised a series of 'drop-in' sessions throughout October for the public to learn more about Ash dieback and our plans to address it. Drop-in sessions have taken place at Sheepleas, Newlands Corner, Norbury Park and KGV Hall, Effingham.

How will Ash dieback be managed?

The Council (Surrey County Council) will focus on managing the risks posed from dying ash trees in high and medium risk locations and it will consider the nature conservation value that ash provides.

The latest evidence suggests that at least 80% of the UK's ash will succumb to the disease, impacting both people and wildlife, presenting a significant risk management and economic challenge to our council budgets.

We recognise our duty to proactively manage the impact of Ash dieback on our own landholdings, as well as promoting good management across the wider county.

We will retain ash trees and monitor their disease progression where safe to do so, and in accordance with our tree risk management policy, only trees considered dead or significantly impaired or deemed a risk will be removed. Where possible timber will be chipped and processed, left at the site in the majority of cases.

We will carry out significant Ash dieback removal works outside of bird nesting season between September and March but will in necessary and specific circumstances, need to remove dead or high-risk trees in accordance with our tree risk management policy during this period, after careful risk assessment and ecological considerations.

We will take action to reduce the landscape and biodiversity impact via the following methods:

Ecological surveys will be undertaken where necessary to determine presence of protected species (for example birds or bats) and where necessary, replacement habitat or mitigation put in place.
Disease resistant trees will be identified, monitored and safeguarded where necessary.
Where appropriate, deadwood will be retained in the form of wood piles or standing habitats as ash trees die or are removed.
Allow for the natural regeneration of ash and for replacement tree cover, where appropriate, when the council will also consider planting native broadleaf tree species, particularly as part of a management plan or under Forestry Commission directive. These trees will be locally, or UK grown and sourced to ensure proper biosecurity (disease prevention). To find out about our target to plant 1.2 million new trees by 2030, see Surrey's new tree strategy.

Finally, the council will be clear in its communications to members of the public, elected councillors and partnership organisations as to why it's carrying out Ash dieback related work on its managed land. We will constantly review the guidance around this disease to ensure work is in accordance with best practice guidance and up to date, based on information from a variety of sources.