Ash Dieback and Tree Safety — Why Dying Ash Trees Are More Dangerous Than You Think

June 23, 2026

Ash dieback (Hymenoscyphus fraxineus) has now been confirmed in virtually every county in England. In Cumbria, the Lake District and across South Lakeland, the disease is widespread and advancing — and the number of ash trees in significant decline or already dead is growing every year. The Forestry Commission estimates that ash dieback could eventually kill the majority of the UK's 80 million ash trees over the coming decades.

Much of the public discussion around ash dieback focuses on the ecological loss — and that loss is genuinely devastating. But for homeowners, landowners, local councils and anyone with ash trees near buildings, roads or public paths, there is a more immediate concern: the safety risk posed by dead and dying ash trees.

This is something we deal with on the ground across Cumbria and Lancashire every week, and the reality is more serious than many people realise.

Why Dead Ash Trees Are Especially Dangerous

Not all dead trees are equally hazardous. A dead oak, for example, can remain structurally sound for many years — the dense, decay-resistant heartwood holds its integrity long after the tree has died. Dead ash is fundamentally different, and this is one of the most important things for landowners to understand.

Ash timber decays rapidly after death. Once a tree has died from dieback, the process of structural deterioration can be surprisingly fast:

Fungal colonisation begins almost immediately — several species of wood-decay fungi colonise dead ash quickly, beginning the breakdown of the sapwood and eventually the heartwood. Ash is particularly susceptible to Armillaria (honey fungus) and a range of other decay fungi that can rapidly compromise structural integrity.
Brittle failure — dead ash branches and stems become increasingly brittle as decay progresses. Unlike a healthy tree, which bends under wind loading, a dead or severely compromised ash stem can fail suddenly and completely, often with very little warning. This type of failure — sometimes called a brittle fracture — can project timber considerable distances.
Root system failure — the roots of a dead ash tree begin to decay along with the rest of the tree, reducing their ability to anchor the stem in the ground. Whole-tree failure (uprooting) of dead ash trees is a real and documented risk, particularly on the wetter soils common across Cumbria and the Lake District.
The problem is invisible — much of the structural decay in a dead ash tree happens internally, invisible from the outside. A tree that appears to be standing reasonably well may be far more compromised than it looks. This is why professional assessment matters — it is not possible to judge the structural condition of a dead ash tree reliably from a distance.

The Speed of Deterioration — Why Acting Early Matters

This is the message we find ourselves repeating most often to clients across Cumbria: a standing dead ash tree is much easier and cheaper to fell safely than one that has already begun to decay.

Here is the practical difference:

A recently dead ash tree — one that has died within the last 12-18 months — can usually be felled using conventional techniques. The timber, while dead, still has sufficient structural integrity to behave predictably during felling.
A tree that has been dead for 2-3 years or more may have progressed to a point where conventional felling is no longer safe. The use of complex rigging, sectional dismantling from the top down, and significantly increased time on site all follow — along with substantially higher costs.
A tree in advanced decay — where the trunk has become hollow or the structural wood is crumbling — may require specialist techniques including the use of a Mobile Elevated Work Platform (MEWP) or specialist climbing equipment, and carries genuine risk for the operatives involved regardless of precautions.

The difference in cost between felling a recently dead ash and dealing with one in advanced decay can be very significant — sometimes several times the price. Acting early is almost always cheaper, as well as safer.

Who is Responsible for Dangerous Ash Trees?

This is a question we are asked regularly, and it is worth being clear:

On your own land — you are responsible for trees on your property. If an ash tree on your land is dead or dying and poses a risk to people or property on neighbouring land, adjacent roads or public footpaths, you have a duty of care to manage that risk.
Trees overhanging roads — Westmorland and Furness Council, the Lake District National Park Authority and Highways England have responsibilities for trees on or adjacent to the highway, but private landowners are also responsible for trees on their land that overhang or threaten the road. If you have ash trees in this situation, the council may serve a notice requiring action.
Tenanted agricultural land — responsibility for trees is usually set out in the tenancy agreement. Both landlords and tenants should check their position.
Churchyards — the Parochial Church Council is responsible for trees in the churchyard. With ash dieback affecting many churchyard ash trees across Cumbria, this is becoming a pressing issue for a number of parishes we work with.

What to Do if You Have Ash Trees in Decline

If you have ash trees on your land in Cumbria and you are concerned about ash dieback, here is the approach we recommend:

Get a professional assessment — we offer free site visits across our coverage area. We will assess the trees, give an honest view of their condition and discuss the options.
Prioritise by risk — not every declining ash tree needs urgent action. We help clients triage their trees by risk level, focusing resources on those closest to buildings, paths, roads and public areas first.
Plan a phased programme if needed — for landowners with multiple ash trees, a phased felling and restocking programme spread over 2-3 years often makes both practical and financial sense.
Check for TPOs or Conservation Area status — ash dieback is generally accepted as grounds for consent to fell a protected ash tree, but you should still apply or give notification in advance where possible. We handle this on your behalf. See our TPO advice page for more detail.
Think about restocking — where ash trees are being removed, replacing them with appropriate native species is both ecologically beneficial and often a condition of planning consent for TPO trees. We can advise on suitable species for your specific site and location in Cumbria.

The Insurance Position

It is worth being aware that home insurance and public liability policies typically require policyholders to take reasonable steps to manage foreseeable risks on their property. A clearly dead or severely declining ash tree near a building, path or road that has not been assessed or managed could be considered a foreseeable risk — with implications for any insurance claim arising from its failure. We are not insurance advisers and you should check with your insurer, but this is a consideration worth being aware of.

Get a Free Ash Dieback Assessment in Cumbria

We carry out ash dieback assessments and felling programmes across Grange-over-Sands, Kendal, Windermere, Ulverston, Barrow, Cartmel, Lancaster, Kirkby Lonsdale and all surrounding areas in Cumbria and Lancashire.

24-hour emergency line for dangerous trees: 07376804724
Email: enquiries@maxreynoldstreeservices.com

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