University of Washington researchers find younger poplar trees could be viable alternative to fossil fuels

In Washington state, a University of Washington team is trying to make poplar a viable competitor to fossil fuels by testing the production of younger poplar trees that could be harvested more frequently—after only two or three years—instead of the usual 10- to 20-year cycle. These trees, essentially juveniles compared with fully grown adults, are planted closer together and cut in such a way that more branches sprout up from the stump after each harvest, using the same root systems for up to 20 years. This method is called “coppicing,” and the trees are known as poplar coppice.

The team is the first to try converting the entire young tree—including leaves, bark and stems—into bio oil, a biologically derived oil product, and ethanol using two separate processes. Their results, published this summer in two papers—one in ACS Sustainable Chemistry & Engineering and the other in Biotechnology for Biofuels—point to a promising future for using poplar coppice for biofuel.