The Worldwide Fund for Nature (WWF) fears that GM trees may lead to silent forests devoid of insects, flowers and birds. It is concerned that GM trees may be more for the profit of a few than for the benefit of humanity at large, and that not enough is known about their potential effect on the environment.

Trees are being genetically modified to reduce lignin content (to make them easier to pulp for paper production), to grow rapidly, to resist pests and rot, or to be sterile. There have been 166 trials on 24 species of GM trees since 1988. Of the 116 trials to date, 70 have been in the US, 31 in Europe and 5 in Britain. The numbers are increasing, with 44 in 1998 alone. The WWF is concerned that commercial planting could begin at any time in China, Chile and Indonesia, and calls for a global moratorium until safety concerns have been properly addressed.

The problems with GM trees are the same as for GM crops, but bigger. Pollen from GM pines could spread 375 miles on the wind rather than three. The longer life of trees also creates far greater potential for environmental damage. The WWF report states: "A combination of time and location factors would allow escaped GM trees engineered for fast, aggressive growth to become invasive weeds with the ability to out-compete naturally occurring vegetation for sunlight, water and nutrients".

There is also the concern that GM tree plantations will increase the use of fertilisers and pesticides.

WWF called on its network of 100 companies who have already pledged to only use timber from sustainable sources to ban GM wood products. Sainsbury's - one of these companies - immediately took the pledge.

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