Trees mysteriously vandalised may pose danger

PUBLISHED : Wednesday, 01 August, 2012, 12:00am
UPDATED : Wednesday, 15 August, 2012, 10:47pm


At least three towering, exotic trees have fallen victim to a mysterious and bizarre act of vandalism that will lead to their slow death - and which could endanger people and property.

The 20-metre tall trees in Siu Lam have fallen victim to ring barking, also known as ring girdling, a practice in which the surface layers of the trunks are stripped away, cutting off the life-supporting phloem that transport nutrients to and from the roots and leaves. The practice is common in rural areas, where it is used to control the growth of trees.

'Ring girdling is [an] ... agonisingly slow way to kill a mature tree,' said Professor Jim Chi-yung from the University of Hong Kong, who warned that the trees could now become a hazard to humans and property as they are likely to die and fall down.

The trees are believed to be swamp mahogany, a species native to eastern Australia, and are located in a densely vegetated area opposite The Castle Bay, a low-rise development at Lok Chui Street. In front of the area is a small, sandy beach facing Lantau Island.

One tree had its bark removed, probably with a saw. The cut is about 2.5cm deep and 5cm wide. The trunks of two other trees had also been cut.

Who carried out the act and why remains a mystery. Many people in rural areas have mastered tree ringing. One theory is that the vandals acted because the trees blocked the view from their properties.

The Tree Management Office under the Development Bureau has said the trees are on private land which is not covered by a tree preservation clause.

The tree killings shocked local residents. One woman, Ann, who did not want her full name disclosed, said: 'It is really bad. How could someone treat nature like this? What was done to the tree is silent killing.'

She said the tree killings were unlikely to be random acts of vandalism, as only one species was targeted.

Ann suspected the fatal damage was inflicted in the week before Typhoon Vicente struck last month, when she saw several men coming out of the bushes with saws.

She said the men were definitely not government officers, as they would normally handle trees sensitively and alert residents when trees were being removed or trimmed.

Ken So Kwok-yin, chief executive of The Conservancy Association, suspected the killing could be related to the views from some properties.

'The tree might have obstructed [some people's views]. After the tree is ring-barked, they can file a complaint to the government and ask [for it to be] cut down,' he said.

So said there had been a similar case in Hoi Ha in the past, during which at least one damaged tree died in less than three months.