The miscanthus planted at Piketon yields 9.6 tons of biomass per acre, according to Islam.
Switchgrass, meanwhile, is a prairie grass native to North America that grows 10-12 feet tall and can also be burned to produce energy or converted to fuel, Islam said. Both miscanthus and swithgrass are propagated via rhizome division or plugs, which can make their initial establishment difficult.
But because they are perennial crops, they can produce biomass for many years before the stands need to be replanted.
Another project at OSU South Centers, funded by the U.S. Department of Energy, involves growing switchgrass and big bluestem grass on a one-acre plot of degraded land where corn and other food crops cannot grow. Researchers are applying municipal biosolids from the cities of Piketon and Chillicothe and gypsum from coal-fired power plants to the soil to increase its fertility and improve drainage, as well as to measure their impact on crop productivity.
Additionally, Piketon researchers are studying the nitrogen requirements of a mixture of prairie grasses (switchgrass, Indiangrass and others), and how many times a year the crop can be harvested depending on the amount of nitrogen applied. Fast-growing hybrid willow trees are also being researched in a half-acre plot.
"These trees are growing in waterlogged, high-clay, high-acidity and overall bad soil," Islam says. "Trees may not provide as much biomass as grasses because it takes several years to harvest them, but they can be planted in areas where nothing else will grow and they can also help improve the soil."
Taller than corn and capable of producing up to 25 tons of biomass per acre, Sudan sorghum grass has been growing at OSU South Centers for the past eight years, Islam said. A related crop, sweet sorghum, was planted for the first time in 2012 at Piketon as part of a collaborative project with the University of Nebraska.
"We can't grow sugar cane in Ohio, but sweet sorghum can produce the same amount of sugar as sugar cane and requires half the nutrients as corn," Islam says. "It is also drought resistant and produces three types of energy: sugar for ethanol or butane, cellulosic alcohol, and biomass that can be used as animal feed or pelletized for combustion."
The last bioenergy crop being investigate at Piketon is guayule, a woody shrub native to the southeastern U.S. Guayule produces hypoallergenic rubber and a hydrocarbon that can be converted into a diesel-like transportation fuel.
"Last year, we successfully managed to grow guayule for the first time outdoors in Ohio," Islam says. "This plant is very drought tolerant, but it doesn't like standing water, so we are growing it in raised beds.
"We are testing this method of growing guayule so that in the future farmers can produce this crop on the hills of southern Ohio."