We're now into a prolonged hot dry spell of weather. When this happens, anxious Duty Holders often get in touch about managing the risk from Summer Branch Drop (SBD), or Summer Limb Drop (SLD), or Sudden Branch Drop (SBD), or Sudden Limb Drop (SLD).
What to do?
The uncertainty about what to call SBD, or SLD, is often matched by similar uncertainty about how you should manage the risk.
Should you put up signs?
Fence trees off?
Prune them?
Fact-checking the risk
The overall risk from SBD is mind-bogglingly low.
From the data, the risk is so low, our risk of death from driving for the few minutes it takes to cover about 5km/3mi is higher than from SBD over a whole year.
Finding a microscopic straw-coloured needle in a gargantuan haystack
Despite this mind-bogglingly low risk, fear-mongering from Risk Entrepreneurs*, claiming legal action is likely if the risk were to happen and it wasn't managed or assessed, has had some anxious duty holders putting up confusing and ineffective signs.
Is standing, lollygagging, or laying down fine?
What we know
We know the overall level of risk from SBD is so low it's Acceptable.
We also know, Arborists can't tell the difference between branches that have a high likelihood of failure from SBD, and those that have a low likelihood of failure.
That means, warning signs make no measurable reduction to a risk that's already Acceptable. In fact, the costs of commissioning and managing these signs are grossly disproportionate to any claimed reduction in the risk.
Linger near trees at your perilPhoto Credit - Paul Barton
Exposing yourself in public
Worse still, the ineffectiveness of these signs may backfire and create an opportunity for a Risk Entrepreneur to act as an expert witness in the extremely unlikely event of someone being killed or injured by SBD. It'd be all too easy for them to claim you hadn't managed the risk well enough, and you could've done more.
Why didn't you put up more signs?
Why didn't you fence the tree off?
Why didn't you prune the tree?
Or, if the visitor wasn't an English speaker, why didn't you translate the sign into other common languages?
If you're a Duty Holder, or advise one, worry not. We've got your back on this one with our Summer Branch Drop Guide.
An antidote to risk entrepreneurs
In short, you don't need to do anything to manage the risk unless you have a repeat offender.
We've also got a whole range of guidance of our Risk Management page.
*Risk Entrepreneur
"Treecare professionals who thrive on maximising the perception of risk in order to create standards for which they are perfectly placed to provide profitable solutions."
Rick Haythornthwaite, Risk & Regulation Advisory Council