An urban tree expert warned that the recent removal of a number of Ho Chi Minh City's towering centenarian dầu trees revealed that many others may be at risk of collapse.
The gigantic pyramidical trees have beautified Saigon's streets for centuries and appear in the lyrics of countless romantic songs about the city.
Last month, when 51 trees in front of the Saigon Opera House were cleared to make way for the city's first underground metro station, many citizens expressed shock and sorrow.
Nguyen Trinh Kiem, a specialist from the Ho Chi Minh City Tree and Park Company, said only two were uprooted and relocated; the rest were axed to be sold at auction.
Ancient trees in front of the Saigon Opera House before being chopped down in late July when construction began on the city's first underground metro station. Photo: Bach Duong
Of the 51 trees, 12 were 150-year old dầu trees (Dipterocarpus alatus), an endangered upper-canopy tree native to Southeast Asia.
Half of the felled dầu trees had lost 60 percent of their roots to decay, said Kiem.
“The trees' taproots had rotted away, so once the workers cut into their lateral roots they came down quite easily,” he said. “This revealed that such trees are at a high risk of collapse.”
Kiem said the drained aquifers along the Saigon River may have contributed to the rotting out of the taproots.
“There are more than 3,000 dầu trees on the city's streets and more than half are roughly 150 years old like the trees felled in front of the opera house,” Kien said. “Some have already collapsed on Nguyen Thai Hoc and Ba Thang Hai streets in recent years. Luckily, no one was injured as the incidents occurred at dawn.”
Dầu trees in their natural habitats may have a lifespan of about 300 years but they aren't as resilient as street trees, he said.
The roots of some
dầu trees in front of the opera house had suffered from significant rot, leading one urban expert to question the structural integrity of another 3,000 such trees throughout the city. Photo credit: The HCMC Tree and Park Company
But Kien said that the rest of the old trees that once filled Lam Son Square--a paved promenade that begins beyond the front steps of the Opera House--should not have been cut down.
“The square's Lim xẹt (rusty shield bearer) and liễu rũ (Callistemon citrinus) trees should have been uprooted and moved to another sites and then replanted along the metro line when construction finished,” he said.
The city plans to clear 57 more trees located in September 23 Park, near Ben Thanh Market, to pave the way for another underground metro station.
Architect Hoang Truc Hao agreed with Kien, saying that old trees are “vestiges," and said an effort to preserve ancient trees should be included in HCMC’s urban master plan. Otherwise, future projects could involve the hasty felling of some of the city's most precious natural resources, he said.
Kien suggested that after construction on the station outside the opera house finishes, a series of trees with shallow root systems should be replanted in the area.
The Ben Thanh – Suoi Tien metro line, which spans nearly 20 kilometers between District 1 and District 9, will run partly underground and partly along an elevated track.
The US$1.2 billion project being funded by Japanese loans is expected to finish in 2018.
In Hanoi, more than 30 ancient trees lining Kim Ma Street in Ba Dinh District will be felled to make room for work on the capital city’s first metro line.
“It’s necessary to sacrifice the trees for urban transit projects. But the green area should be restored [after construction work is complete]," said senior architect Hoang Dao Kinh.