Researchers at Wageningen University in the Netherlands have found that DNA testing can accurately identify illegally logged and traded tropical hardwood.
The study was published recently in the journal Biological Conservation and shows the potential use of genetic markers as “forensic tools” to enforce laws governing the timber trade, according to the authors.
Illegal logging is a significant problem in the tropical hardwood trade, with anywhere between 30 and 90% of all tropical hardwood logged illegally.
According to Wageningen University researchers, existing tests to determine the origin of tropical woods are not very effective since documentation is often fraudulent. The scientists therefore wanted to evaluate the potential of chemical and genetic wood characteristics to differentiate Tali timber, an African wood species, from one forest concession to the next.
Researchers collaborated with two logging companies to collect 394 wood samples in five different forest concessions in Cameroon and Congo-Brazzaville. Using those samples, the scientists created a reference database, against which they could compare new timber samples for the tests.
Genetic specialists at the university were then asked to run blind tests on 12 timber samples to determine their origin. The tests correctly identified where the samples came from 92% of the time, which is “a great score,” according to lead author Mart Vlam of Wageningen University’s Forest Ecology and Forest Management Research Group.
Their tests also showed high geographical accuracy. The method was able to correctly differentiate timber originating from forest concessions that were only 14 kilometres apart.
The scientists said this level of precision is crucial for identifying illegally logged wood since forest concessions in which logging is permitted often border those in which it is prohibited.
“The fact that we can accurately differentiate the origin of timber down to a 14 kilometre radius is new,” said Vlam. “Previous studies only managed to do that on a much coarser scale.”
The authors say their results highlight the potential value genetic analysis has for forensic testing of tropical hardwood, as well as for enforcing timber trade laws. However, lead researcher Pieter Zuidema cautioned that “a lot needs to be done before these tests can be used as evidence in court.”
In Europe, bilateral trade agreements between the EU and 15 tropical timber exporting countries are designed to stop the illegal timber trade and include efforts to verify the legality of timber that is exported to the EU. In 2016, the EU imported around €716 million worth of tropical hardwood from those 15 countries, with nearly a third of coming from Cameroon.
The scientists intend to conduct further research to help their method become a viable tool for identifying illegally logged hardwood.
“We need to collect timber samples from a much larger area and our analyses and labs will have to meet strict criteria,” said Zuidema. We can’t do that on our own, so we are collaborating in a worldwide network of researchers, labs and authorities.”