FAQs

About dangerous trees and the damage that they cause

Q. I am worried that a tree is dangerous - what should I do?

A. If you own the tree you should have it inspected by a competent arboriculturist and follow his/ her advice. If the tree is in someone else’s ownership then you should initially express your concerns to them. If you are unhappy with the response you receive from the landowner then you can contact your local district council. They may be able to require the owner to carry out any necessary work under the Miscellaneous Provisions Act (1976); but only if the tree is imminently dangerous.

For more information, contact a professional arboriculturalist, your local district or borough council planning department, or your solicitor.

Q. Is a hollow tree a dangerous tree?

A. In many cases large hollow trees are no great cause for concern as decay is part of the natural life cycle of species such as Oak and Ash. In fact hollow trees are often extremely robust if otherwise healthy (a cylinder is a very strong structure yet as it is hollow has less weight to support). All truly ancient trees are hollow and may have stood as such for hundreds of years, but the overall condition of the tree needs to be assessed. Often of more concern are younger trees which are showing signs of disease and decay and perhaps becoming hollow - these trees are unlikely to be able to tolerate this process and may become significantly weakened. If you are in any doubt over the safety of a tree then you should contact a professional arboriculturist.

For further information, contact a professional arboriculturalist.

Q. Is a swaying tree a dangerous tree?

A. When a tree sways in the wind it is often taken as a sign that it is becoming unstable. This is in fact rarely the case. Trees sway in the wind to dissipate the wind’s energy and therefore the movement is not usually a cause for concern. If you are concerned about a tree you might watch the ground around its base on a windy day to see if you can detect signs of ground movement ("heave"). "Heave" often leaves radial cracks along the root lines, or "arc" cracks where roots have snapped. Sometimes it leaves a raised mound of soil on the windward side of the tree. If you can detect "heave" there is likely to be a problem and you should seek professional advice. It can be surprisingly difficult to judge whether it is the ground or just the stem moving!

For more information, contact a professional arboriculturalist.

Q. Do trees damage foundations and drains?

A. Damage to foundations is relatively uncommon in Shropshire. Tree roots have little to gain from entering these dry and hostile environments. Occasionally tree roots may affect foundations built on very heavy clay soils or peats, as they remove ground water causing the soil to shrink and foundations to slump. This is called subsidence and may have many causes. Large trees growing very close to buildings are the most likely to cause problems. Direct damage by stem or root expansion is even more unusual, except to light structures such as paving slabs which are readily displaced.

Drains are only directly affected when they are already damaged, allowing roots to penetrate. The roots can then grow through any cracks or loose joints to form a tightly woven mass which may block the drain. Subsidence can also affect drains.

For more information contact a professional arboriculturist or a structural engineer / drainage expert.