CHIANGRAI TIMES – More than 100,000 wild Himalayan cherry trees in Chiang Rai’s Doi Chang are about to die due to an agrobacteria, according to Sa-ngiam Phailom, a researcher at Doi Wawee Highland Agricultural Research Centre.
The disease started spreading about five years ago, but this year the situation has worsened as almost all of the trees are affected, he said.
”The outbreak spread fast because our station at Doi Chang is full of the wild Himalayan cherry trees as we have planted them for two decades. In addition, there are no other types of trees to break the spread of the disease,” he said. Like a monocrop plantation, when one gets infected, others follow suit.
Agrobacteria are natural plant parasites carried by birds or wind. The bacteria inserts its genes into plant hosts, which causes them to form a proliferation of cells on their trunks. This blocks nutrition from the soil as well as water reaching the branches of the trees, eventually causing death.
”When the trees are strong, the bacteria can do no harm. But when the trees are more than 10 years old, they are weak and vulnerable,” Sa-ngiam said, adding that the other Himalayan cherry trees in Doi Tung and Doi Mae Salong also share the same unfortunate fate.
However, the bacteria does not cause any harm to humans.
To deal with the outbreak, he said they had considered two solutions. The first was to use chemical insecticide. ”But there are too many trees and using insecticide can cause future problems,” he said. The second option was to burn infected trees. ”This method is also impossible to carry out,” he added.
So the staff at the centre agreed to return to square one.
”When we started the centre 20 years ago there were only a couple of Himalayan cherry trees in the area. We collected the seeds and planted them, leading to the thousands we now have,” he said. What is happening today is a typical circle of the tree that when it reached peak time, it will die and then be reborn.
Although visitors might not be able to have the picturesque view of pink cherry blossoms all over the mountain during January, they can still enjoy other things when they visit Doi Chang.
Sa-ngiam said the station, which is 1,500 metres above sea level, would still be beautiful with other types of flowers such as poppies, petunias and begonias as well as fruits such as strawberries and apricots. There are also nice spots to watch the sunrise with a sea of mist and sunset views over the mountains.
Doi Wawee Highland Agricultural Research Centre can be only reached by pick-ups or four-wheel vehicles. It is located in Mae Suai district.