Clemson, ArborGen testing poplars as bioenergy sources

By ArborGen Inc. | December 27, 2012

Scientists at two of South Carolina’s most recognized names in forestry and biofuels research plan to find out if poplar trees grown in South Carolina have a role in the nation’s bioenergy future.

Researchers at Clemson University’s Pee Dee Research and Education Center and Ridgeville-based ArborGen Inc. have collaborated to plant thousands of poplars at the Pee Dee center to determine if certain varieties of the tree are suitable for bioenergy stock.

David Brown, ArborGen's southeastern field research manager, noted that biomass for bioenergy gives landowners another market for their crops.

“Clemson’s Pee Dee center plays a vital role developing bioenergy markets by growing a variety of bioenergy feedstock,” Brown said. “In the case of this project, we are working to determine the absolute best tree for bioenergy and having that available to South Carolina forest landowners.”

Last year, ArborGen planted four species of poplars at the Pee Dee center. Some of those trees already have grown taller than 20 feet and show great promise for emerging bioenergy markets worldwide, Brown said.

In November, Brown and his collaborator at Clemson, crop physiologist Jim Frederick, planted 690 varieties of Populus nigra (“black poplar”) to learn which are best suited as bioenergy stock and as “parents” for making hybrids with P. deltoides, the local eastern cottonwood that grows healthily in the U.S.

Brown and Frederick planted more than 3,000 trees, which they will monitor and evaluate during the next few years. The approximate rotation length—time between harvests—is about five to six years, by which time some may be more than 50 feet tall, Brown said. The trees will sprout again and grow from the cut stumps, thus they need to be planted just once.

In 2009, Clemson and ArborGen formed a research cooperative that centered on development of purpose-grown woody biomass as feedstock for the biofuels industry.

Clemson and ArborGen collaborate in such areas as plant genetics and development, field trials, equipment engineering, material handling and woody biomass pretreatment, among other areas.

Research is conducted on tree species that include coastal loblolly pine, sweetgum, eucalyptus and poplar trees as possible sources of renewable biofuel.

Clemson’s Frederick said much of the woody biomass for bioenergy likely will come from purposely grown bioenergy trees that have fast growth rates and is an important area of research for Clemson to be involved in.

“Interest in bioenergy as a whole is the basis for the partnership,” Frederick said. “There’s no big grant involved—just two groups working together for a common cause.”