INCENSE trees on eastern Shenzhen's Wutong Mountain, listed as a category II protected plant in China, are endangered due to heavy exploitation for profit.

More than 40 incense trees, or aquilaria sinensis, are dying on the mountain and the number is increasing, a Shenzhen Evening News report said yesterday.

The resin extracted from the wood is used as a valuable Chinese medicine called Chen Xiang.

According to Chinese medicinal literature, the resin can be extracted in large quantities by natural fungal infection or by external wounding (up to 5 centimeter into the bark). Sustainable harvesting of the resin of one tree can be carried out by opening a wound 3 to 4 centimeter into the bark, and with the resin collected a few years after accumulation.

"One kilogram of balm is sold for 30,000 to 40,000 yuan (US$4,225 to US$5,834) on the black market," a staff member with the management office of the mountain said. "It is quite profitable."

The office said the situation was becoming worse despite the deployment of more patrols on the mountain.

In August 2006, a man in his 30s was caught carrying a bag full of resin. He was sentenced to a four-year jail term. He was among a number of people caught trying to smuggle resin out of Wutong Mountain park, most of whom were from Gaozhou and Dianbai cities in Guangdong.

"I think the trade should be very prevalent there," a park employee said. "Huge profit is behind the reason why they had come such a long way here to steal the resin."

"It normally takes at least 30 years for a sibling to grow into a incense tree," an expert surnamed Zeng said. "It is painful to see that they are destroyed."

According to China's Criminal Law, people who destroy and illegally exploit precious plants could face jail terms varying from three to seven years.

The plant is endemic to China, and can only be found in Jinhong in Yunnan Province, Guangdong Province, Hainan Province and the Guangxi Zhuang Autonomous Region.

(Mu Zi)