SHANGHAI, Aug. 25 -- SHANGHAI researchers have established a database featuring 50 foreign harmful plants and insects in the battle to keep China's agriculture free of disease.

More than 40 foreign noxious plants and species such as the North American yellow flower Canada Goldenrod and the American Smooth Cord Grass have already been discovered in the city.

The spread of plants like this threatens agriculture, forestry and health and leads to a loss of three billion yuan (US$389.6 million) every year, according to the Shanghai Landscape and Gardening Research Institute.

Researchers at the institute are working on a special Website which will provide information on the 50 plants and species including photographs, characteristics, distribution and advice on prevention and control.

"We spent three years on the establishment of the information platform," said Li Yuezhong, the chief engineer at the institute. "In the near future residents will be able to go to the database whenever they discover some unidentified plant or insect. If it looks harmful residents should immediately report this to the institute."

"We hope residents will help us to guard against noxious foreign species," said Ju Ruiting, another engineer at the institute. "They can learn about the dangers and the plants and species on the Website and once they encounter something suspicious they might be able to help prevent a disaster."