Kew’s Tree Library Leads Hi-Tech War On Illegal Logging

The wooden blinds that lie crumpled in Peter Gasson’s laboratory in Kew Gardens are chipped and forlorn-looking. Their manufacturers had claimed they were made of pine, but customs officers were wary. And their suspicions were well-founded. Gasson, Kew’s research leader on wood and timber, found the blinds were not made of pine but ramin. “All ramin trees, which grow in south-east Asia, are endangered and trade in their wood is illegal,” said Gasson. “On this occasion, we got lucky and stopped people profiting from this trade.” But elsewhere, illegal logging threatens to overwhelm the timber trade. It is estimated that almost 30% of sales are made up of illicitly sourced timber. More than 20,000 square miles of forest are being chopped down illegally every year, according to WWF, the wildlife charity, to provide furniture and flooring for people’s homes. The devastation is jeopardising the planet’s ability to absorb carbon dioxide and is destroying the habitats of endangered animals including orangutans and tigers. As a result, researchers at Kew have joined conservationists, such as the Forest Stewardship Council (FSC), to set up the Global Timber Referencing Project to create a scheme to identify important forests and create a database for identifying timber sources. “A lot is being done to reduce illegal logging by setting up audit systems to certify timber supply chains,” said Roger Young of AgroIsoLab, another project partner. “But these efforts are compromised because paperwork systems are fallible, and until now there has been no way to verify the origin and species of timber once it has been harvested. The new project aims to put that right.”

The project has two arms. First, scientists working at Kew will confirm the exact species of a tree from samples sent to it, said Gasson. “The laboratory already has many thousands of timber samples in its vaults but these will be increased with new samples for the new identification project,” he added. Once this has been established, other reference collections will be set up in other countries. For example, Kew will receive more than 200 new samples, collected by the FSC, from commonly traded wood species in Nicaragua, Honduras, Guatemala and Peru this year. The aim is to create a massive tree reference library at Kew, whose samples and expertise can then be distributed to other laboratories. “This is a unique opportunity to develop a library of geo-referenced wood samples,” said Michael Marus of the FSC. Being able to spot the species of a tree is not sufficient to curtail illegal logging, however. The location of that wood’s growth is also crucial. “All ramin trade is illegal, so identifying the material in imported goods is sufficient to have them impounded, but other woods are more complex,” Young said. “It is different with teak. Trade from Thailand is allowed, but the same wood from Myanmar is illegal. So we need to be able to spot where a sample of teak was grown.”

AgroIsoLab scientists will use patterns of isotopes of oxygen, nitrogen and carbon that are found in wood to pinpoint their exact places of growth. “Soil in an area produces a specific isotopic signature that we can recognise,” he told the Observer. “We already use this technology to pinpoint sources of food, such as bacon. We can tell from a rasher’s isotopic signature whether it comes from Britain or from Denmark. And that is important. Bacon from Denmark is cheaper because standards of pig care there are lower and so we can spot when cheap Danish bacon is being sold as the expensive UK variety.” The new project aims to do exactly the same for wood. “We want to be able to take a sample – oak from furniture, beech from flooring or pine from a table – and provide its true identity and place of growth,” said Young. “If we can do that, we have a chance to halt illegal timber sales.”

Credit: Robin McKie for The Guardian, 24 February 2019.