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THE first paper has been made from genetically modified trees despite an attack on a stand of GM poplars by environmental activists. The trees yield slightly more paper with the use of less chemicals.

To make paper, one of the two main components of wood, lignin, must be removed. This is usually done by heating with alkalis and bleaching. To make the process more efficient, an international team funded by the European Union modified poplars so their lignin would break down more easily. Stands of the trees were planted in France and Britain in 1995. In 1999, those in Britain had to be harvested several months early after they were damaged by activists.

The team has now published the results of its field trials. The best variety required 6 per cent less alkali to process, while pulp yield was up by 3 per cent, says team member Claire Halpin of the University of Dundee. The trees grew normally, although their roots decomposed more easily.

Their qualities should be attractive to industry. But conventional breeding over the past two or three decades has probably produced even greater gains, points out Graham Barnard of Britain鈥檚 Paper Federation. And how much further the GM strains can be improved isn鈥檛 clear. More drastic modifications have hindered growth.

Activists worry that large stands of altered trees could harm forest ecosystems. But the team found no significant differences in soil chemistry or bacteria under the GM trees.

Not everyone is convinced that the trees are as tough as normal, though. David Andow, an entomologist at the University of Minnesota, points out that the rate of insect attack was so low for all trees in the study that it鈥檚 hard to tell how the GM strains would tolerate serious infestations.

The experimental strains won鈥檛 ever be grown commercially. But the team does now plan to produce other GM strains of poplar and pine for paper production.

Environmentalists question the need for such trees, saying chemical pulping should be replaced with more eco-friendly options. But these methods are more expensive and produce lower-quality paper.