Five of Hong Kong's heritage trees, some of them ancient, are in danger of death and collapse, according to a green campaign group.
The Conservancy Association said the five trees - a Chinese banyan in Kowloon Park, a West Indies mahogany in Hong Kong Cemetery, a rain tree on Shouson Hill Road, a silk tree in Sham Shui Po and a banyan in Kowloon City - were showing an increasing number of cracks in their trunks and a noticeable loss of leaves and were leaning to one side.
The trees were among the nine chosen as the city's top trees in a public vote in 1997.
"We really need a comprehensive policy that emphasises preventive measures instead of just saving and removing trees," said Ken So, the association's chief executive.
The Kowloon Park banyan - believed to be the source of an epidemic of brown root-rot disease spreading through trees in Tsim Sha Tsui - is still plagued by fungi and pests, despite being placed in what the Leisure and Cultural Services Department described as "intensive care".
A departmental spokesman insisted it had shown no sign of further deterioration.
"We have been applying fungicide every three months and organic foliar liquid fertiliser is also applied every 15 days to supply nutrients to the tree," he said.
Sections of another infected tree nearby have been left exposed for at least a week after its collapse in Typhoon Vicente. Leaving these sections exposed could allow the fungal virus to spread on the wind and the epidemic to spread further in the district, experts said.
The South China Morning Post reported last week that the government had covered up the city-wide attack of brown root rot, known as "tree cancer", and its own failure to contain the spread of the disease.
The Tree Management Office and specialists confirmed the epidemic was threatening trees in at least seven areas - Tsim Sha Tsui, Central, Happy Valley, Lei Yue Mun, Aberdeen, Diamond Hill and Tung Chung.
Now trees in Tuen Mun, Yuen Long and Ma On Shan have been found to be affected too.
Tree specialist Jim Chi-yung, of the University of Hong Kong, said it was unacceptable that the banyan in Kowloon Park, estimated to be more than 400 years old, had fungus on its branches and was losing its bark under the government's care.
He said: "The sanitation measures were also very poor. They should take the same approach in trees to treating any infectious disease in people. The first step to containing the epidemic should be disclosing information - telling the public how widespread the situation is. There's no way that the health of trees can be held confidential."
Jim added he was not being kept fully informed, despite sitting on an official panel of tree experts.
The Leisure and Cultural Services Department spokesman also said a termite problem with the Kowloon Park banyan had been successfully contained last year.