Signs a tree in your garden could be dangerous

Published 25 October 2026

Most garden trees are perfectly safe, and the risk of anyone being hurt by one is very low. The Health and Safety Executive says between 5 and 6 people a year are killed in the UK by falling trees or branches, and it describes the risk from trees near busy areas as roughly one in 10 million. But big trees are heavy, and a branch dropping onto a patio, a car on the drive or a neighbour’s roof can do real damage. Knowing what to look for means you can deal with a problem while it’s still small.

Who is responsible for a tree?

The owner of the land it grows on. Stockport Council says a tree in a neighbour’s garden or on other private land “is the responsibility of the owner of the land”, and that if you’re worried about one, your first point of contact is that owner. Cheshire East Council, which covers Wilmslow, Poynton and Knutsford, gives the same advice and adds that tree owners “should take reasonable care to inspect trees regularly”, and that owners found to be negligent can be held liable for injury or damage.

You’re not expected to guarantee a tree will never fail. The National Tree Safety Group (NTSG), whose guidance is published through the Forestry Commission, says the standard is that of a reasonable and prudent owner.

How often should you check your trees?

The NTSG’s leaflet for tree owners suggests walking round your garden once a year in late summer or autumn. If your trees look sound and healthy with no obvious defects, that’s all you need to do. It’s also worth a look after a storm. Late summer is useful because the tree is in full leaf, so dead branches stand out.

Warning signs to look for

Dead branches or a dead tree. The NTSG says a tree or branch with no leaves on it in summer is probably dead. Dead wood becomes brittle and can drop without warning, which is why deadwooding is one of the most common jobs on mature trees over lawns, paths and parking spaces.

Fungus on the trunk, branches or around the base. Bracket fungi are the ones to take seriously. The RHS says they cause decay in the heartwood, and that by the time a bracket appears there has usually been extensive internal decay. Some decayed trees go hollow and stay standing; others break or fall. The RHS names a few to watch for:

• Meripilus giganteus (giant polypore), mainly on beech, which is especially dangerous because the whole tree may fall
• Ganoderma species, on a wide range of trees
• Laetiporus sulphureus (chicken of the woods), often seen on oak
• Inonotus hispidus (shaggy polypore), on ash, apple and other broadleaved trees

Honey fungus is different. The RHS says the signs are white, sheet-like fungus between the bark and the wood near ground level, black “bootlace” cords in the soil, and branches dying back. Its honey-coloured mushrooms only appear in some seasons, in late summer or autumn, so no mushrooms doesn’t mean no fungus.

Cracks and splits. The NTSG says cracks in branches, the trunk or the ground may need checking, as may daylight showing through a split in a limb or fork. A crack in the soil on one side of the tree can be a sign the roots are moving.

A rocking or lifting root plate. If the base of the tree moves in the wind, or the ground heaves on one side, the roots may be failing. The NTSG lists “a rocking root plate” among the defects most people would recognise. It also warns that damage to roots, such as from digging for a new drive, patio or extension, may not show for years but increases the risk of failure.

Ash trees thinning from the top. Ash dieback is now widespread across Greater Manchester and Cheshire. Bare twig tips in the crown, blackened leaves in summer and clusters of new shoots along the trunk are all signs. Infected ash becomes brittle, so see our page on ash dieback if you have an ash near the house.

What to do if you spot something

Don’t climb the tree or try to cut out a large or high branch yourself. The NTSG advises calling a competent tree surgeon if a dead branch is large or at height, or if you find a fungus and aren’t sure what it means. Keep people and cars away from the area under it in the meantime.

A problem doesn’t always mean the tree has to come down. Depending on what’s found, a crown reduction can take weight off a weak limb, deadwooding can deal with the dead branches, and tree removal is kept for trees that can’t be made safe.

If the tree is a neighbour’s, Stockport Council’s advice is to speak to them first. Our guide to neighbours’ trees that overhang your garden explains what you can cut back yourself.

What if the tree is protected?

Check first. If a tree has a Tree Preservation Order, government guidance says you must give the council 5 working days’ written notice before working on a dead tree. For a tree that’s an immediate risk of serious harm, written notice must be given as soon as practicable after the work becomes necessary, the work should only go as far as needed to remove the risk, and the danger must be present, not just possible. In both cases the owner has a duty to plant a replacement. The guidance suggests getting advice from an arboriculturist or confirmation from the council before relying on these exceptions. See our protected trees page and our guide to whether you need permission to cut down a tree in Stockport.

Council and street trees

If the worrying tree is on a street, in a park or on other council land, report it to the council rather than the owner of the nearest house. Stockport Council has an online form for reporting tree problems, and you can attach photos. If any tree is touching or close to overhead power lines, Cheshire East Council directs people to SP Energy Networks, or 105 in an emergency. Don’t go near it.

How our teams help

Whether it’s a beech with fungus at the base in Bramhall or an ash dropping twigs over a drive in Marple, our teams can take a look and talk you through the options, from deadwooding to reduction or removal. Get a free quote and tell us what you’ve noticed.