DR Jim Chi-yung has a room with a view. From his office, the tree expert looks out to the lush mountain greenery that skirts across one end of the Hong Kong University campus. But this view is fast disappearing. Dr Jim, university reader in soil science and biogeography, who himself graduated from the HKU in 1975, says the university was once surrounded by trees on a mountain slope. Today, there is only a hint of green near a pond enveloped by tall buildings.
Pointing outside his windows, he says: 'I can see the greenery disappearing on campus because we have to build more to accommodate our teaching needs. We need to build more to accommodate all sorts of activities now.' This saddens Dr Jim who, since his student days, has had a special fondness for trees and nature. However, it is the grey reality of modern development and redevelopment which prompted him on his mission to save the city's trees from further destruction.
Two years ago, the Urban Council commissioned Dr Jim, 42, to produce a five-year tree planting plan which aimed to inject more green into the dull, concrete jungle. Having submitted the last, and sixth, volume of a survey report this month, he has produced a comprehensive study and plans to preserve, and plant more roadside trees in the city. The $400,000 project took two years to complete. The first part contains detailed information on 20,000 roadside trees, such as their crown spread, trunk diameters, height and dimension, and growing space. It also measured environmental impacts on roadside tree growth such as the traffic volume, the nature of buildings and its density.
Dr Jim says this part of the survey is for data analysis and management. Should any roadside tree need urgent attention in future, data would be available immediately. But it is the second-half of the project which promises to change the territory's urban outlook. Throughout, Dr Jim scouted for locations suitable for planting trees. A total of 12,000 potential sites were found, but he believes not all will be used. 'When looking for suitable sites, we wanted to see if the pavement and roadside are wide enough or if they are free from obvious obstructions,' he said. 'But not all sites can be used as we didn't carry out underground studies. Such an exercise would be too complicated and time-consuming for the project. Under our pavements, there are various utilities' lines like pipes and cables. So around 7,000 to 8,000 sites can be used.' The next step is to choose the right species for the selected sites. And Dr Jim, who obtained his doctorate in soil science from the University of Reading in England in 1981, is fastidious about what should be planted where. 'Each planting site will be for a specific species based on various criteria like the dimension of the plant space and the conditions for plant growth,' he explains. 'I will also look at the surrounding land used. For instance, large sites along Lung Cheung Road are near the hillside so I can plant species like the Chinese banyans, or lemon-centred gum, or big-leaved banyans there.' But that's not all. Dr Jim will also try to increase the colour of the city by introducing some colourful and rare species such as flame of the forest, red kapok, and the blue Persian lilac. He believes the Hong Kong climate is perfect for growing trees. 'I'll try to select species that give us more flowers and seasonal colours and changes in terms of foliage. Season changes are important for us. At the moment we have too many green and evergreen trees. We have a humid, tropical, monsoon type of weather and we have more than 2,000 tall trees. We should make use of the climate. The only unfortunate thing is typhoons. We have trees that are prone to destruction by strong winds.' However, Dr Jim believes it is the artificial, rather than natural causes that damage trees in urban areas: 'We have all sorts of environmental and atmospheric stress such as air pollution, heat, and dry air in the city. There is also . . . artificial lighting. But the most important [cause] is the lack of growth room on our roadside locations. That is why the trees can't achieve good performances. We also have the problem of buildings and roads being too tightly built together.' In recent years, Dr Jim has been fighting hard to save two ancient banyan trees on Sports Road. Instead of just cutting them down, the Jockey Club has agreed to have them transplanted to Wong Nai Chung Road. 'The Jockey Club is moving the two beautiful trees on Sports Road,' he said. 'But they really should be in situ rather than moved. It's dramatic to the old tree, a lot of them are over 100 years old.' Although he lives with his wife in Pokfulam, and enjoys the countryside, Dr Jim says people are under great stress, created by their city life, and believes it is very important to improve the environment, and therefore, the quality of life. 'One way to do that is to introduce nature in the city,' he said. 'I don't think it's impossible.' Dr Jim believes that greenery should not be confined to the countryside alone, the city can be connected with it by 'green corridors'. 'Rather than just eliminating the negative impacts like pollution we should look to introducing positive elements in [environmental protection],' he said.
