HAMBURG - Scientists in Germany are unleashing a new tool to stop illegal wood trafficking: DNA tests. Labels, after all, can lie. DNA doesn't.

Germany imports up to 6 million cubic meters of illegal wood every year – roughly the volume of 2,400 Olympic-sized swimming pools, according to Professor Mattias Dieter of the Hamburg-based Thünen Federal Research Institute for Rural Areas, Forestry and Fisheries.

Cracking down on the illegal wood trade is no easy task, especially since rules about what exactly makes a piece of wood legal or not are themselves complicated. "Illegal" can mean several things, ranging from wood types listed in the Endangered Species Act to wood from trees felled in protected areas. In some cases the wood comes from legal trees, but was prematurely – and therefore illegally – harvested.

Proving what woods are illegal in Germany is made even more difficult by the huge number of legal woods traded – some 600, explains Gerald Koch of the Thünen Institute for Wood Technology and Wood Biology.

But there is one way to nail down the real origin of a piece of wood: examine its particular genetic makeup. Thanks to his trusty computer and a collection of 50,000 samples, Koch and his colleagues in Hamburg can provide, usually within hours, the exact information on wood type from any sample provided by customs, importers, builders, or private individuals.

In some cases the purpose of the examination is not to establish illegality of the wood, but fraud, as when sellers claim a wood is a particularly valuable (and more expensive) type when this is in fact not the case.

"In the next few years, hundreds of new types of wood are going to be coming on to the market, many of them lesser known species," says Koch, who expects that over time DNA testing – which is presently possible but more time-consuming and expensive – will become more routine. Such testing is presently conducted only when it is necessary to establish the country or region a specific wood comes from.

Genetic testing is "a high art"

Bernd Degen, who heads the Thünen Institute for Forest Genetics, says that DNA testing makes it possible to follow the whole chain of a wood from felling to finished product. The DNA of a tree cannot be changed or faked.

Extracting the DNA from wood is "a high art," he says. Degen is tight-lipped, however, when it comes to the details of the procedure he follows as he is currently applying for a patent. He does explain that for the method to become routinely used, wood samples from regions around the world have to be collected, analyzed and data-processed.

With his team, Degen has been traveling to Africa, South America and Russia to collect samples; in every location, samples are taken from 30 trees to create a solid statistical base. As one research project in Cameroon showed, DNA analysis can determine the provenance of wood to within 50 km of where it originated.

"Our goal here in Hamburg is to build, over the next three years, a data bank containing the genetic codes of 50 species of trees," says Degen. From there, a German "Wood Identification Competence Center" can be developed.

Read the original story in German by Norbert Lossau

*This is a digest item, not a direct translation

Photo - D H Wright