Many of Tokyo’s popular and iconic Somei Yoshino cherry blossom trees were planted during Japan’s postwar advancement in the 1960s, and are now getting old and frail.Some have fallen, and many others require support, triggering safety concerns as the Japanese celebrate the season of their favourite flower. Two cherry blossom trees collapsed on Thursday, one at Kinuta Park in downtown Tokyo and the other at the Chidorigafuchi greenway.The one in Kinuta Park damaged a fence while the other tree almost fell into the Imperial Palace moat, though nobody was injured.The tree in Kinuta Park was 18 m (59 ft) tall and 2.5 m (8.2 ft) in diameter. It was among the oldest, believed to be more than 60 years old, officials said. In March, another old cherry tree collapsed at the park, injuring a passerby.Last year, 85 trees fell in Tokyo parks, injuring three people, and many were cherry trees, according to Masakazu Noguchi, a Tokyo metropolitan official in charge of public parks. People gather under the trees during the season of hanami, or cherry blossom viewing, and the collapse of trees has alarmed officials in Tokyo, the birthplace of the cherry blossom variety.Tokyo assembly member Yutaka Kazama expressed concern on social media last month that “cherry blossom trees with their roots partially exposed or obviously rotten seem dangerous”, calling for firm safety measures but without quickly resorting to tree felling.A tree doctor, Hiroyuki Wada, said, “Many trees in our daily lives were planted soon after the war and are now 70-80 years old and getting weaker.” He said they were affected by extreme heat in the summer and an extensive dry season.“I hope people think about climate change through what’s happening to the cherry blossom trees, which is very symbolic,” he said. Following the March incidents, officials conducted tree health checks at Tokyo’s main parks ahead of the cherry blossom viewing season.At Kinuta Park, officials have conducted preliminary inspections of more than 800 cherry trees. They chopped down a number of trees and posted warning signs near some trees, but the tree that fell on Thursday was without caution signs. “At the moment, our measures are mostly temporary, not fundamental steps such as replanting,” Noguchi said. “We call on visitors to use caution because we cannot say it’s safe even after inspection.”