Organised from the USA, the International Society of Arboriculture (ISA) convened a group of more than 50 international experts to produce a best-management practice document called Tree Risk Assessment (www.isa-arbor.com). It focuses on the practicalities of inspecting trees and purposely steers away from broader risk management.
In the UK, the National Tree Safety Group (NTSG) took a different approach, with an emphasis on principles rather than practical details. Its composition was different, too, dominated by stakeholders with a vested interest in the contents of a tree-management guidance document. Published under the title Common Sense Risk Management of Trees (www.forestry.gov.uk/publications), this initiative aspires to "develop a nationally-recognised approach to tree safety management".
As a practical guide to help tree inspectors identify problems and decide what to do, the ISA document is an obvious success. It is intuitively structured, which makes it easy to follow, and its language is pitched to communicate effectively on a practical level. This is a technical publication that is easy to understand for those inspecting trees on a daily basis. In short, it is a useful contribution.
In contrast, the NTSG document is a confounding mixture of muddlement and confusion, interspersed with occasional glimpses of brilliance that are undoubtedly its saving grace. In particular, the section on the law is not to be missed, but the rest fails to match that standard. This inconsistency makes it a work in progress rather than the finished article. But is improvement possible?
It is rumoured that there will soon be a new NTSG steering group, but drastic changes will be needed if it is to move forward. The ISA model may offer some clues. Get rid of the influences of vested interest, bring in the experts who know about the detail, take proper account of the legal context and find an independent leader to take control. The NTSG was a well-intended experiment that has not delivered. It is not over yet, but now it has to evolve or surely fail.
Jeremy Barrell is managing director of Barrell Tree Consultancy.