An Appeal Court decision has set a costly precedent for local authorities over damage caused by trees, says Roger Pearson

The recent dry summers have played havoc with the foundations of properties throughout the UK and subsidence has become common.

Home-owners have learned to their cost that trees, which they may have been told posed no risk of damaging their property, can nevertheless wreak havoc because their roots are struggling to draw water from parched ground.

The roots' demand for water can drain soil, leaving it so dry that it can damage foundations. So who pays the price for the the long, hot summers?

In the light of a recent Court of Appeal decision, it looks like local authorities may be forced to pick up the tab for the damage. It leaves little doubt that councils could end up paying a high price for tree-lined avenues in their districts.

And local authorities which did not plant the trees, but took responsibility for them after they became established, may also have to pay out.

The case, which has sent ripples of concern through town halls up and down the country, is the first major tree-root litigation for years and is regarded as a signpost ruling in an area where case law is sparse.

The action centred on a claim over a semi-detached house built in 1954 at Fareham in Hampshire.

John McDonald, who with Dermod O'Brien QC represented the householder whose property was damaged, says the ruling will concentrate the minds of those in town halls on the harm that trees can cause.

"Local authorities are bound to be concerned at the decision," says McDonald. "It means they can be held liable for damage caused not only by trees planted by them, but also for trees for which they have assumed responsibility but which they did not plant."

He adds: "It is a case which may pose a dilemma for some local authorities. They will need to carry out a fine balancing act in deciding whether to keep some trees which make their roads look attractive, or remove them because of the fear of the damage they could possibly cause."

Standing outside the Fareham house is an oak tree believed to be about 190 years old. In the dry summer of 1989 the house began to suffer serious structural damage and the owner claimed this was caused by subsidence, which was in turn caused by the roots draining moisture from the clay soil.

At Southampton County Court, the home-owner's claim against Hampshire County Council was upheld by Mr Recorder Meggeson, who held the county council responsible for the harm caused by the roots of the oak tree.

He awarded damages of £78,823 against the council, and this award was upheld by Lords Justice Stuart-Smith and Morritt and Sir John Balcombe in the Court of Appeal.

The council argued through counsel Simon Russen that the tree was not the property of the council, but belonged to the owner of the subsoil its roots were in (that is, the owner of the property fronting the street).

However, Lord Justice Stuart-Smith made it clear that the court took the view that if a tree is growing in the verge of a highway which has been dedicated to the public, the local authority becomes responsible for damage caused by the roots.

The judges dismissed the argument that householders who own subsoil stretching out from their property were responsible for such trees. Lord Justice Stuart-Smith said whether trees were planted or self-seeded on the highway, they were the responsibility of the authority.