Tree Risk Assessment Survey

  A Tree Risk Assessment uses the Quantified Tree Risk Assessment (QTRA) method to evaluate the risk a tree presents in a clear, standardised, and defensible way. QTRA is a nationally recognised approach that focuses on the target, meaning the person or property that could realistically be harmed, rather than the tree in isolation. A tree standing in an empty field presents no meaningful risk to anyone. The same tree next to a busy footpath is a different matter entirely. QTRA quantifies that difference objectively.

The assessment considers three factors: the likelihood of a part of the tree failing, the size of the potential failure, and the probability of it striking a target. These are combined to produce a Risk of Harm figure, which is then benchmarked against HSE guidance on acceptable levels of risk to members of the public. This produces a proportionate, evidence-based conclusion rather than a cautious recommendation made simply to avoid a difficult decision.

Importantly, QTRA is as useful for demonstrating that a tree can be safely retained as it is for identifying genuine risk. A tree with visible defects or unusual features is not automatically a problem. The method allows those features to be assessed on their merits, and often supports retention where a less rigorous approach might default to removal.

A Tree Risk Assessment also fulfils your duty of care as a tree owner or occupier under the Occupiers’ Liability Act 1984, and can help managers of larger sites prioritise budgets and focus resources where the risk is genuinely highest.

Tree Risk Assessments are provided across Somerset, North Somerset, Bristol, and South Wales.

For more information about QTRA please visit www.qtra.co.uk.