Ash Dieback in West Sussex: What Homeowners Need to Know

If you have an ash tree in your garden, and across the Crawley area, tens of thousands of gardens do. This disease concerns you directly. Ash dieback (caused by the fungus Hymenoscyphus fraxineus) has spread through West Sussex's ash population over the past decade, and the county's woodland and hedgerow ash are now visibly thinning. Most infected trees will decline over several years; a proportion die quickly.

How to spot it

Look for these signs, easiest to see in summer when the tree should be in full leaf: dieback in the crown: bare, leafless branches at the top while lower growth survives; blackened, wilted leaves that hang like burnt tissue rather than dropping; diamond-shaped dark lesions on the bark where branches meet the stem; and dense clumps of new shoots lower down the tree, a stress response as the tree tries to regrow beneath its dying crown.

Why a declining ash is more dangerous than other dead trees

The awkward truth about ash dieback is that infected wood becomes brittle. A dead oak can stand safely for years; a dead or dying ash sheds large limbs without warning and becomes progressively unsafe to climb. That has two practical consequences. First, an ash near your house, drive, garden path or a public footpath needs assessing sooner rather than later. Waiting makes the eventual work more dangerous and therefore more expensive. Second, badly infected ash often can't be climbed and dismantled the normal way; they need felling in larger sections or handling from a platform, which is why a heavily declined ash costs more to remove than a healthy tree of the same size.

What to do if you suspect it

Don't panic and don't rush to fell. Early-stage infection doesn't automatically mean removal, and some ash show useful tolerance. The sensible sequence: get the tree assessed; check whether it's covered by a Tree Preservation Order or sits in a conservation area (see our guide to TPO rules in the Crawley area). Protected trees still need consent even when diseased, though a genuinely dangerous tree has an emergency exemption; then act according to condition. Light infection may just mean monitoring annually. Significant crown loss near a target. House, road, play area, usually means planned removal while it can still be done safely.

If a declining ash near your property is worrying you, we can take a look: tree removal and tree surveys are both handled by insured local professionals. For a tree that's already shedding limbs, treat it as urgent. Call 01293 310077 and see our emergency tree work service.

Replanting

Losing an ash doesn't have to mean a bare garden. Good native replacements for West Sussex's clay soils include field maple, hornbeam, small-leaved lime and wild cherry. We're happy to advise when we quote.