The law about neighbours' rights and responsibilities for trees is covered by the common law of nuisance. Where the branch or root of a tree comes onto a neighbour's land, a nuisance situation exists. The law of nuisance may provide several remedies depending on whether the tree has caused, or is likely to cause, actual damage or loss. In most instances, and unless the tree is a significant tree, the neighbour can remove the encroaching roots or branches. This would usually be at his or her own cost, as the cost of removing the branch or roots cannot be claimed unless the work is necessary to minimise damage which is already occurring or is likely to occur. The neighbour cannot go onto the tree owner's land and cannot remove any part of the root or branch that is not on his or her property. The branches and roots are technically the property of the tree owner and can be placed back over the fence, taking care not to cause any damage.
If the intruding roots or branches have caused damage to the neighbour's property (for example, roots cracking pipes or branches damaging gutters or poisoning animals) the neighbour can ask the tree owner to pay the cost of repairs or compensation. If the tree owner is unwilling to pay, the neighbour can apply to the Minor Civil Actions division of the Magistrates Court for a court order that the owner pay. In some circumstances a court might order that the owner remove the root or branch or perhaps the whole tree. Advice should be sought.
Problems often arise when tree branches fall, causing damage. The owner's responsibility in these situations depend on whether the tree was overhanging the boundary. Where an overhanging tree or branch falls, the tree owner would be liable if the damage caused was reasonably foreseeable. To hold the owner responsible for a tree that was not previously overhanging the boundary or where the tree was overhanging public land such as a road it is necessary to show that the owner knew or should have known that the tree or branch was in a dangerous condition and that it might fall and cause damage.
A neighbour who is aware that a tree near the boundary is in a dangerous condition, or belongs to a species which is known to ‘drop’ branches, should draw this to the tree owner’s attention in writing and keep a copy of the letter. If damage occurs later, this will assist to establish that the tree owner was aware of the problem and failed to take reasonable and appropriate precautions. If, however, a strong, healthy tree blows down across the fence in a storm, this is considered to be an ‘act of God’ for which there is no liability. Nor is there liability for leaves, needles, nuts or twigs which are blown into the neighbour’s property by the wind unless, perhaps, they were known to be highly toxic and attractive to animals or children.
See also our booklet Trees and the Law available from our Publications page.