Ash trees are everywhere in our part of Kent. They line the lanes around Detling, Stockbury and Bredgar, fill the hedgerows below the North Downs, and stand in many of the larger gardens in Bearsted and Hollingbourne. Sadly, a great many of them are now affected by ash dieback.
If you have an ash tree on your property, it pays to know what the disease looks like, when it becomes a safety problem, and what your options are. This guide explains the signs to look out for through the year and what to do if you think your tree is infected.
What Is Ash Dieback?
Ash dieback is a disease caused by a fungus called Hymenoscyphus fraxineus, which originally came from Asia. It was first confirmed in Britain in 2012, and the south-east of England has been one of the worst affected areas. Kent County Council confirms the disease is now infecting ash trees across the county.
The fungus spreads on the wind. Spores are released in summer from tiny fruiting bodies on fallen ash leaf stalks, land on the leaves of nearby trees and work their way into the shoots, branches and eventually the trunk. The Woodland Trust estimates that the disease will kill up to 80% of ash trees in the UK. There is no known cure, although a small proportion of trees appear to show some tolerance.
How to Spot Ash Dieback Through the Seasons
Spring
Ash is one of the last trees to come into leaf, so a bare ash in April or May is not necessarily a sign of disease. By mid-June, though, a healthy ash should be in full leaf. Watch for parts of the crown that stay bare, or branches that produce only small, sparse tufts of leaves.
Summer (July to September)
This is the best time to check your tree. Look for:
- Dark patches on the leaves, which then wilt and turn black.
- Leaves dropping early.
- Shoots and twigs dying back, especially at the top and edges of the crown.
- Clumps of new growth sprouting from the trunk or lower branches (known as epicormic growth), which is a sign the tree is under stress.
Autumn
Take care at this time of year. Normal autumn colour changes can be confused with the disease, and bunches of dark ash keys (seeds) left hanging after leaf fall are normal on healthy trees too. Summer is a much more reliable time to judge the leaves.
Winter
Once the leaves have gone, it is easier to see the shape of the crown. Signs to look for include:
- Dead twigs and branches, and a thin, “stag-headed” crown.
- Dark brown, diamond-shaped lesions on the bark, often centred where a side shoot or branch joins the stem. These can be seen at any time of year.
- Lesions or fungal growth at the base of the trunk. In heavily infected areas, ash dieback can weaken the tree enough for secondary infections such as honey fungus to take hold.
Why Infected Ash Trees Become Dangerous
As an infected ash declines, its wood can lose strength quickly, particularly where honey fungus or other decay is also present. Dead and dying ash becomes brittle and is prone to dropping branches or failing altogether, sometimes with little warning. The Forestry Commission notes that decline can happen in as little as two growing seasons.
This matters for two reasons. First, a falling limb can cause serious damage or injury, especially over a driveway, road, footpath or play area. The owner of the land where a tree stands is legally responsible for the safety of people who could be affected by it. Second, the more brittle an ash becomes, the more dangerous it is to climb and work on. Dealing with a declining tree sooner is usually safer, and often simpler, than waiting until it is completely dead.
If a tree has already dropped a large branch or come down, we offer emergency call-outs 24/7. Our guide on what to do when a tree falls explains how to keep everyone safe while you wait.
When Does an Ash Tree Need to Be Removed?
Not every infected ash needs to be felled. Official guidance is to keep ash trees where it is safe to do so, especially those that look healthier than the trees around them, as they may have some natural tolerance. In some cases, crown reduction, deadwood removal or pollarding can make a tree safe while keeping it standing.
Removal is more likely to be the right answer when:
- The tree is near a house, road, footpath, power line or anywhere people regularly pass.
- A large part of the crown has died back.
- There are lesions or decay at the base of the trunk.
- The tree has already shed large branches.
A qualified tree surgeon can inspect the tree and give you an honest view on whether it can be managed or needs to come down. Where work is needed, guidance for Kent suggests that, where possible, felling or pruning infected trees should be done after leaf fall.
Do You Need Permission to Work on an Ash Tree?
Ash dieback does not automatically remove the need for permission. Before work starts, check the following:
- Tree Preservation Orders and conservation areas. If your tree is protected, you normally need consent from the council, or must give notice in a conservation area, just as with any other tree. A tree that is dying, rather than dead, still needs the normal permission. For a dead tree, at least five working days’ written notice is usually required. Only where there is an immediate risk of serious harm can urgent work go ahead first, with the council told as soon as practicable. Parts of Bearsted, Detling and Hollingbourne are conservation areas, so it is always worth checking. Our guide, Do I Need Permission to Cut Down a Tree in Maidstone?, explains the rules. Bredgar falls under Swale Borough Council rather than Maidstone. We can help with the application or notice, with a charge depending on how complex it is.
- Felling licences. Trees in private gardens do not need a Forestry Commission felling licence. However, if you own woodland, paddocks or larger areas of land, a licence may be needed to fell diseased ash unless the trees are dead or pose a real and immediate danger.
- Trees next to roads. If an ash tree stands beside a road, Kent County Council asks owners to have roadside trees regularly inspected, and the Tree Council advises contacting the highway authority before work is carried out.
- Wildlife. Ash trees can be home to nesting birds and bats, which are protected by law. See our guide on nesting season for more on timing.
Planning for the Future
If you lose an ash tree, it is worth thinking about what to plant in its place. The Forestry Commission encourages replanting with a mix of species, which helps gardens and hedgerows cope better with future pests and diseases. Our guide to the best trees to plant in small gardens in Kent is a good place to start.
Frequently Asked Questions
Can ash dieback be cured?
No. There is currently no known cure or effective treatment, although a small number of ash trees appear to tolerate the disease.
What is the best time of year to check for ash dieback?
Mid to late summer, from July to September, when leaf symptoms are clearest. Bark lesions and dead branches can be seen at any time of year.
Does every ash tree with ash dieback need to be felled?
No. Trees that pose little risk can often be kept and monitored, or made safe with pruning. Removal is usually needed where a declining tree is close to buildings, roads, footpaths or power lines.
Do I need permission to remove an ash tree with ash dieback?
If the tree has a Tree Preservation Order or is in a conservation area, you will usually need consent or must give notice to the council. Trees in private gardens do not need a felling licence, but woodland may.
Is a dead ash tree dangerous?
It can be. Dead and dying ash becomes brittle and can drop branches or fail without much warning, and it also becomes more dangerous to work on, so it is best to get it inspected sooner rather than later.
Worried About an Ash Tree?
If you think an ash tree on your property has ash dieback, our NPTC and City & Guilds qualified team can inspect it and advise on the safest option, working to British Standard BS 3998. We cover Maidstone and the surrounding villages, including Detling, Bearsted, Hollingbourne, Stockbury, Bredgar and Grove Green.
Quotes are free and with no obligation, and taking the waste away is included as standard. You can also send us a video of the tree on WhatsApp for a quick first opinion.
📧 Email: office@maidstonetreesurgeons.co.uk
☎ Office: 01622 925926
📱 WhatsApp: 07375 455138
