Chidlom tragedy sparks calls for tree care improvements
Experts weigh in on necessary steps to ensure there is no repeat of fatal accident, writes Supoj Wancharoen
Trees, especially large ones, are often seen as natural symbols of strength, but like man-made structures they can become dangerous and possibly fatal if left neglected without proper and adequate care.
Consider the incident on Bangkok’s Chidlom Road on the morning of May 13. A mature tree, that had weakened over time due to inadequate care, became uprooted, toppling seven electric poles which subsequently killed a woman riding her motorcycle, injured two others and damaged a few more vehicles on the road.
Responding to the incident, arborist Taradon Tunduan demanded state agencies and the private sector fully understand the key concepts of urban forestry and arboriculture, and how important they are to the city. The practices involve trimming trees and shrubs to protect roadways, power lines and pavements.
Mr Taradon criticised people and organisations for having limited knowledge of arboriculture. Many harbour the misconception that all trees require similar maintenance, which resulted in some arborists in Thailand using inappropriate care techniques for tropical plants.
“One size does not fit all when it comes to caring for trees. Each type of plant requires different strategies to maintain their health and appearance,” he said.
He said different types of plants require different environments, adding as an example that mangrove trees are more tolerant of being submerged than a plant native to cold climates.
He encouraged people to learn about tree biology to ensure their plants perfectly fit the urban landscape.
Trees interact with environmental changes including changes in soil, light, temperature and moisture. With proper care and maintenance, trees can survive and thrive in a new environment, he explained.
It is important to understand how trees react to changes in their environment. If we alter the environment, it may be stressful to them, he added.
An arborist must have insight into different species of plants and their biological aspects, Mr
Taradon said.
Common causes of trees being uprooted in storms and high winds are rotten roots, rotten trunks, and inappropriately trimmed heavy tops, Mr Taradon pointed out.
“So, we have to check if there is an open wound in a tree or whether the trunk is big enough to support the tree top or if the top is balanced,” he said.
Mr Taradon urged the BMA to examine street trees throughout the city and determine whether the plants have structural defects which are likely to cause problems in all or part of the tree.
Something must be done about hazardous trees, he said.
He also urged the BMA set up a special unit that includes experts on urban forestry, saying officials at the Department of Forestry have the potential to handle urban forestry work.
He cited Singapore’s National Parks Board which was once chaired by its late former prime minister Lee Kuan Yew.
Once formed, the unit can work closely with educational institutions including Kasetsart University’s Faculty of Forestry which can provide information regarding care and maintenance for tropical plants.
The BMA should also improve state officials’ skills by holding training programmes on basic urban forestry and best management practices for relevant officials.
Officials in different state agencies, such as the Department of Highways and the Metropolitan Electricity Authority, whose jobs are associated with gardening, care and maintenance of street trees, should be invited to join the programme to ensure that they fully understand the key concepts, techniques and challenges of urban forestry, Mr Taradon said.
Agencies responsible for caring and maintaining trees must regularly examine them in their jurisdiction and write a tree safety report for a long-term management plan.
Oraya Sutabutr from the Big Trees Project, an environmental advocacy group, blamed poor maintenance, professional incompetence in urban forestry and carelessness for the accident.
“Tree risk assessment procedures can be complicated. We do not have enough gardeners who have the skills and years of experience to do the job,” she said.
Urban trees with their roots hidden under concrete or asphalt surfaces are vulnerable and require a high level of care and maintenance.
Ms Oraya called on authorities to find sensible ways to deal with weak trees that may pose a danger to the public or property instead of felling them.
“Cutting down trees should be the very last resort,” she said.
She praised the BMA for its efforts to solve urban tree problems as the agency had arranged training programmes on street tree management for their gardeners.
“But more work needs to be done,” Ms Oraya said, urging gardeners to take their job more seriously.
The BMA should be more proactive with the training programme while tree care and maintenance should be carried out regularly, not only in the rainy season, to reduce risks, she added.
Deputy governor Chakkaphan Phewngam said he had ordered each district office to examine city trees and follow a six-step guide to taking good care of them.
The six steps, according to him, include fertilising the trees to bolster their health; preventing and treating tree diseases; pruning trees to maintain their health and appearance and nurturing the roots; supporting weak trees to protect them from storm damage; trimming trees; and removing trees that are dead and dying or those that grow around power lines to avoid unwanted uprooting.
Mr Chakkaphan urged authorities to assess each tree carefully to see whether it needs to be supported or removed, saying the assessment procedure is one of the most important steps in arboriculture practices.
“We do not want to cut down trees. We promote the nurturing of trees which can help reduce air pollution,” he said.
Currently, there are some 3,116,660 trees in the city which are maintained by the BMA, with most of them having limited root space, increasing the likelihood of uprooting, Mr Chakkaphan said.
He also urged the public to contact the 1555 hotline if they find a tree that is in danger of falling.