This old pine tree in Haidian district, which was in need of rejuvenation, fell down before work could be carried out. [China Daily]

While old trees in Beijing are getting treatment as part of the city's rejuvenation program, experts are expressing concern about the effects of environmental degradation on the city's most ancient residents.

The program, which was launched in the middle of September and is due to finish by Nov 20, covers old trees in all 16 districts and aims to rejuvenate 500 trees in two months, of which 300 are in Haidian district.

"In Haidian district, 4.6 million yuan will be spent on saving old trees," said Zhang Yu, a press officer with the Haidian district bureau of landscape and forestry.

The amount of money is almost 10 times that of previous years, she told METRO.

Beijing has more than 40,000 registered old trees, 85 percent of which are under 300 years old, typically pine trees, cypress trees and ginkgo trees.

Twenty percent of them are in declining health and 2 percent are endangered, said Yang Zhihua, head of the Wildlife Protection Department at the Beijing Municipal Bureau of Landscape and Forestry, who leads the rejuvenation program.

"They are regarded as living fossils and are non-renewable once destroyed," Yang said.

The protection program includes supports for leaning trees, soil improvement, nutritional supplements, tree hole repair and exterminating pests, said Cao Hengxing, general manager of a website featuring experts in the rejuvenation of old trees.

Cao said that although rejuvenation is considered an advanced and expensive technique in many countries, in China it is done by engineering companies under the direction of experts who examine every single tree carefully before making a diagnosis and applying a specific treatment.

"The cost of treating an old tree varies from 5,000 to 500,000 yuan," Cao said. "But old trees are so valuable that, whatever the cost, it is worth it."

Deterioration of their environment is the main reason for the premature decay of the capital's old trees, said Xu Gongtian, who leads the rejuvenation program in Haidian.

"Many construction projects in the past few decades have caused dramatic changes to the flow of the underground water, thus indirectly affecting the provision of water to the roots," explained Xu, who is in his 70s.

"The winter chill and continuous drought in summer are also bad for old trees."

Xu said that human activities such as piling up garbage or putting up houses around trees have also affected the trees' well-being and the rejuvenation program is the last chance to save the them.

"Trees are like humans, if we take good care of our health every day, there's no need to visit the doctor," he said.

Both Xu and Cao think the biggest problem is the lack of awareness of how to protect the trees.

However, Xu is optimistic about the fate of old trees because of a new regulation on the daily maintenance of old trees that is being launched by the city's Bureau of Landscape and Forestry by the end of 2010. "I'm looking forward to reading the draft. I hope it ensures the daily care of every specific kind of old tree in Beijing," he said.

There is no international standard regarding the definition of old trees. In China, it means trees older than 100 years, but in some other countries, the age is 50.

(China Daily October 26, 2010)