Testing diverse woody plants for biomass crops

Photo: Gary Kling

Jan. 21, 2011, Urbana, IL – University of
Illinois researchers are studying novel and traditional woody plants as short
rotation crops for biomass production.

“Diversification of your plant materials
for biomass production is sound from an ecological standpoint: A greater
diversity of species minimizes the risk from serious disease or insect
outbreaks that could threaten a large percentage of production when only a few
species are utilized,” says Dr. Gary Kling, associate professor in the Department
of Crop Sciences, and one of eleven researchers collaborating on the study.
He says there is a wealth of ecological niches and climatic
zones where biomass may be produced someday, and likely a wide range of species
that will be best adapted to these varying environments.

“The most commonly studied woody plant
genus for biomass production (poplar) was selected for pulp production in the
manufacture of paper,” Kling says. But he adds that characteristics that make a
plant good for paper are not necessarily those that make a plant good for
energy production. Plants for paper production are typically grown for 12 years
before being harvested and replaced. However, for bioenergy repeated production
is needed from the same plants over a much longer period of time, he says.

“We do not know how the various species,
poplar and willows included, will respond to repeated cutting and production
over a 30-plus-year production system,” he says.

The team of researchers from the
Energy Biosciences Institute at the University of Illinois selected plants for
study based on their coppicing ability, adaptability to the environment,
potential for biomass accumulation, non-invasive status, few major limiting
pest and disease problems, availability, and inclusion in the U.S. Department
of Agriculture database.

Kling says that woody plants offer many
advantages as a feedstock for biofuel production. “Woody plants typically have
a lower ash content when burned as compared to grasses, thus reducing the
amount of waste generated. In addition, grasses usually have higher
chlorine content than woody plants, which can be damaging to boilers.”

The plants chosen for the study include red
maple, silver maple, thinleaf alder, river birch, hybrid chestnut, northern
catalpa, common hackberry, bloodtwig dogwood, American filbert, American
smoketree, possumhaw, American sweetgum, tuliptree, osage-orange, sycamore,
eastern cottonwood, black cherry, scarlet oak, flameleaf sumac, black locust,
and sherburne willow.

Two-year-old seedlings were planted in the
spring of 2010 and will be grown for one to two seasons before cutting back to
induce coppicing, Kling says. Then they will be grown for a three- to five-year
harvest cycle. Researchers will collect growth and environmental data to
determine if these woody plants can serve as short rotation crops for biomass
production.