Tree lovers are being asked to act as 'green spies' in support of a campaign for a law to protect trees and plants from poor care and the threat of urban development. The Conservancy Association yesterday called on the public and organisations to identify a tree in their district and report any damage to trees under their stewardship. The call came after an 8-metre branch of the Wishing Tree in Tai Po, overburdened with oranges and Lunar New Year wishes snapped off on February 12, injuring a 62-year-old man and a four-year-old boy. It also comes after recent reports of damage to valuable trees on a North Point site awaiting development. Those taking part in the programme will have to visit the trees regularly and take pictures of them. Text or photographic records should also be sent to the green group for archiving. The association hopes to raise public awareness on tree protection and push for a monitoring network across Hong Kong. It has also written to 10 leading developers and relevant government departments seeking their support for a tree protection law that would lay down clear rules and responsibilities in protecting, managing and caring for trees in the city. A signature campaign has been launched, with people being asked to sign leaf-shaped submissions and hang them on a paper tree. The association will present signatures to officials on Earth Day on April 22. 'We hope developers and the officials give us a clear answer whether they support such a law. We will also show them the public is very keen and in favour of this legislation,' said association chief executive Lister Cheung Lai-ping. Lung Ying-tai, a visiting professor at the University of Hong Kong, said a law was vital to raise public awareness. She said developers and government departments were the two main 'killers' of trees and that a protection law should be a top priority on the agenda of the acting Chief Executive Donald Tsang Yam-kuen. Jim Chi-yung, chair professor of the geography department at the university, also supported the law, saying the existing system and departmental bureaucracy were both inadequate and unclear in protection trees. He said over the past 10 years 56 trees aged more than 100 years had been lost due to various causes.