The giant camphor tree in She Shan Tsuen, Tai Po, is heavy with age. Steel beams support its branches, some of which are 25 metres above the ground. The tree is several centuries old and a two-metre cavity at its base is a testament to its many years.
Brian French, an American arborist and tree climber, dangles from one of the climbing ropes that festoon the canopy as he prunes dead branches and inspects the tree for disease. French and his assistant, Kelvin Chan Kwok-hin, work quietly, accompanied by the occasional rasp of a saw. Below the canopy the forest floor is damp and gloomy with shade. At one point the silence is shattered by the roar of a chainsaw as they trim a large branch.
'Don't cut it too close to the live part,' French calls through the canopy to Chan, who is wielding the chainsaw. If French had his way he would not be pruning any of the dead wood.
'It's important to leave dead wood in older big trees,' French says, explaining that it can be difficult for older trees to heal from pruning and that bad pruning can lead to disease and rot.
'There's some plants growing on this one,' French says, as he pokes at the aged wood. 'And there are bugs and birds that live on the branch. Taking away the dead branch is taking way the habitat of these plants.'
But dead branches pose a danger to the public and French's preventative work is being repeated across Hong Kong in a burst of arboreal activity that began in March last year, when the Development Bureau established a greening, landscape and tree management section. The Tree Management Office (TMO) is one half of that section, which was created to push a new policy on making Hong Kong greener. The entire section has an annual budget of HK$40 million and 30 staff.
The TMO came about in part because of alarm over casualties caused by falling trees. The collapse of a 23-metre coral tree in Stanley Market in 2008, which killed student Kitty Chong Chung-yin, 19, was a powerful catalyst, sparking a task force investigation led by then chief secretary Henry Tang Ying-yen. But the fact that French is clambering up some of the more than a million trees scattered across Hong Kong's urban public places is a symbol both of the efforts the city is making to deal with any problems they may pose and the difficulties it has in finding skilled arborists locally to deal with those problems.