SINGAPORE: The heritage Tembusu tree that fell at the Singapore Botanic Gardens on Saturday (Feb 11), killing one person and injuring four others, was last inspected and found to be healthy in September last year, according to the National Parks Board (NParks).
The 40-meter-tall tree was uprooted at the edge of the Palm Valley in the Botanic Gardens, bringing palm trees around as it fell. According to NParks, the tree is over 270 years old, established earlier than the garden.
NParks added that, as the Singapore Botanic Garden heritage tree, trees are checked twice a year – more often than other trees in the garden.
“Trees also have a lightning rod and fence to prevent visitors from pressing the root zone, and leaves are usually applied to the root zone to promote healthy root growth,” it said.
Lead Arborist Ng Tze Peng says a range of factors – the environment, climate and the state of the trees – may cause trees to fall.
“Due to its slow growth characteristics, Tembusu is known for its hard woody structure.” “Age does not mean that the tree is structurally weakened – it may be damaged by the growth process along the tree, Decay and weaken.
“To ascertain the cause of the accident, the authorities must study the structural condition of the whole tree, in particular the root system, the environmental and climatic conditions at the time of the incident,” he added.
Tan Huan Arboriculture Services managing director Andy Tan said he would expect a tree this old to have been inspected every month, to ensure that issues such as fungi and termites did not set in.
Nonetheless, he said it was unlikely that fungi or termites were the cause of the incident. These issues could take up to one or two years to weaken such a big tree enough for it to fall, and tell-tale signs such as unhealthy leaves or termite tracks would be evident months before, according to Mr Tan.
The tree expert’s opinion was that the most likely cause of the tree toppling was water-logging due to recent heavy rains. This could result in the surrounding soil loosening and the roots rotting. Strong winds during storms could have further exacerbated the problem, he added.
“Still, you would seldom see this for the Tembusu tree as they have very large roots … their base is very strong.”
NParks is investigating the cause of the tree falling.
