Transgenic poplars could make China a big player in lumber. But some experts worry about effects on nature.
By Mark Clayton
Scattered across at least seven provinces in China are more than 1 million common poplar trees with an uncommon bite. They can kill the insects that nibble their leaves. Their unusual defensive system is a genetically engineered bomb: Bacillus thuringiensis, or Bt, a naturally occurring toxin inserted into the tree's DNA. Other such transgenic species, such as the larch and walnut, are in the works, Chinese researchers report.

Such moves are shaking up the twin worlds of forestry and environmentalism. Transgenic trees are reaching the threshold of commercialization - a point bioengineered crops reached in the 1980s, observers say. This time, though, it's not the United States leading the charge, it's China.
Though little reported in the West, China's swan dive into large-scale transgenic forestry is essentially the first commercial-scale deployment of genetically engineered (GE) trees in the world, experts say. That could one day mean a potent new competitor to the lumber and paper industries. It also may mean that cutting-edge GE tree research in the US will fall behind, hobbled by regulation and public protest. It also puts decisions about a controversial - and, some say, potentially dangerous - technology into the hands of an authoritarian government, with less oversight and fewer technical controls than in the West.
"What the Chinese have done, planting [genetically engineered] trees across hundreds, maybe thousands, of acres, hasn't been done anywhere else in the world," says Yousry El-Kassaby, a forest geneticist at the University of British Columbia in Vancouver. "It marks a shift in the center of gravity away from the US, where there's a lot of genetic engineering tree research, but much of it is restricted to the labs or very regulated small field trials."
The case for GE trees seems straightforward. Faster-growing species can produce more lumber and paper in shorter time, which makes them a cheaper raw material. Supertree plantations could also mean less disturbance of natural forests - an environmental plus.
Scientists can "develop faster-growing trees, trees that produce more biomass that can be converted to fuels, and trees that can sequester more carbon from the atmosphere or be used to clean up waste sites," said Spencer Abraham, then US secretary of Energy, last fall.
Proponents also tout the technology as something that can be used to return vanishing species such as the American chestnut to the American landscape, by modifying its genetic makeup to defeat a devastating blight.
A problem with pollen
But there's a big catch, experts warn. Trees are perennial plants that produce large quantities of pollen released far higher into the air than ordinary crops. This "gene drift" in crops has caused problems as large seed companies have sued US and Canadian farmers for illegally using GE seeds. The farmers claimed their crops were contaminated by drifting pollen, but to no avail. A study last year by the Union of Concerned Scientists found that seeds of traditional varieties of corn, soybeans, and canola "are pervasively contaminated" with low levels of DNA from genetically engineered varieties of those crops.
If DNA can spread so broadly from GE crops a few feet high, there's no telling what will happen with pollen from trees 50 to 100 feet high or more, experts say. For example: Pollen from GE conifer trees can blow more than a thousand miles, new research at Duke University shows.
The potential for genetic contamination of forests - and potential rewards from using GE trees - are enormous, experts say. "For the first time, we have the ability to put a bacteria or even a fish gene into a tree," says Robert Jackson, professor of biology and director of Duke University's Center on Global Change. "Some make that a moral issue. Is it morally right? Another question is: Is it smart - or, maybe, is it dangerous?"
Indeed, the idea of releasing GE trees into the wild sends shudders through Alyx Perry of the Southern Forests Network, a coalition of loggers, landowners, and environmentalists. "Our conclusion is that the genetically engineered trees will inevitably contaminate nongenetically engineered stands of trees."