To enforce laws and treaties that protect endangered tree species, federal agents first have to recognize those species when they come across wood they suspect came from illegal logging operations. A US Fish and Wildlife Service lab has spent a decade developing a mass spectrometry approach to rapidly identify wood by species. Now the scientists are taking it on the road. Some years ago, David Gehl went to Siberia. “I went to lots of sawmills and forests and came back from Russia and China with 20 kg of wood boards,” he recalls. Gehl was part of an undercover probe by the Environmental Investigation Agency (EIA) following up on suspicions that oak imported into the US from China had come from eastern Russia where logging was prohibited. …With Gehl’s evidence and other information, federal agents obtained a search warrant and raided the headquarters of Lumber Liquidators (now called LL Flooring).