The father of a New Zealander who was killed by a falling tree branch at Kew Gardens in London has spoken of his desire to have summer branch drop recognised worldwide.
Chris Wilson's daughter Erena Wilson died at Royal Botanic Gardens, Kew in September 2012 after a cedar tree branch fell on her following a storm.
Tree consultant Jeremy Barrell, working for the Wilson family, blamed summer branch drop, the rare phenomenon that causes branches to fall when heavy rain follows drought.
However, a jury found that the death was an accident with summer branch drop not the cause, and Kew was not at fault.
Despite the finding Wilson is now campaigning to have visitors to public gardens warned about the dangers of summer branch drop.
He said: "I'm a lay person but the more it came to light and the more research we did about it independently and with Jeremy Barrell's assistance the more it became a worldwide thing.
"In different jurisdictions around the world they seem to take it a lot more seriously than in Britain. It's one of these things where people say it's a freak with only one in millions of chances of happening, but so is an avalanche and many other things. I don't see why it's not more widely recognised."
He said actions to stop death from summer branch drop "don't have to be a huge thing" such as fencing off trees. He suggested gardens open to the public put up website warnings after long dry spells when weather conditions may be conducive to falling branches.
Wilson also said signage at entrance or signs next to trees that grow over major walkways would be useful and need only be in place for six-to-eight hours after sudden downpours. He added: "I don't want to be fist shaking at Kew. It's about awareness into public domain."
Following the inquest, held in London in June, Kew horticulture director Richard Barley said: "The jury had found that there was no identifiable cause of branch failure from this tree which caused this accident.
"As noted by the independent expert in this case, there was nothing that could have been foreseen, no action that he felt could or should have been taken and the trees were being managed in an entirely appropriate and responsible way."
Research paper Potential options outlined
Jeremy Barrell will be publishing a paper on summer branch drop in late 2014.
He said it "may be more frequent than first thought and that, contrary to what some sources are stating, it may be possible to focus in on vulnerable trees and identify certain times of the year when the risk is greatest. If this turns out to be correct, then it opens up the possibility of reasonable and proportionate management precautions to reduce the risk."
He added that precautions will be dictated by the specific circumstances of each tree but options may include "subtle pruning, general internet warnings, localised warnings near trees or at property entrances and temporary or permanent fencing".