Regenerative agriculture: Miscanthus a growing market

SYCAMORE, Ill. — Perennial crops are key tools for regenerative agriculture.

“In our prairie systems, most of the carbon in the soil used to be in the air — it didn’t come from the rocks,” said Emily Heaton, professor and director of the Illinois Regenerative Agriculture Initiative at the University of Illinois.

“Carbon dioxide from the atmosphere is absorbed into plant tissues using the power of the sun and the plants store energy in the form of carbon bonds,” said Heaton during a presentation at the Illinois Crop Management Conference hosted by U of I Extension at the DeKalb County Farm Bureau building in Sycamore.

“That energy is released later when you eat the plant or burn the plant and a decent amount of that carbon goes into the soil,” the university professor said.

“When plants do this they release water, so they de facto mediate the water cycle in the Midwest,” she said. “Something like 70% of our rainfall comes from evapotranspiration, which is really different from people on the coasts that get most of their rain from the ocean.”

Midwestern farmers have a lot of opportunity to capture value from their land.

“Right now, we don’t have anything on our fields so we have missed opportunities to capture value from our resources,” Heaton said. “Soil is capturing energy in the form of heat with our black soil, but it’s dissipating at night when it cools off.”

Sometimes people forget that plants are efficient and self-sustaining solar collectors.

“About 6% of the sunlight that hits the earth can be captured in plant tissues and that’s basically free energy,” Heaton said. “Crops are the only thing that can help mediate carbon and water cycles, so they provide a lot of useful functions.”

When plants grab carbon from the air, it not only goes to plant biomass, it also feeds the microbiome that lives in the soil.

“And perennial crops are a useful tool for keeping water in your field,” Heaton said.

At the Energy Farm on the U of I campus, researchers are growing switchgrass, miscanthus and energycane.

“We work on energycane because it’s a relative of miscanthus,” Heaton said. “And miscanthus has been researched in Illinois longer than anywhere in the U.S.”

Miscanthus is currently being used as a fuel source for the University of Iowa power plant.

“They are more heavily dependent on coal than they want to be, and in 2012, they couldn’t get coal,” Heaton said. “They already burn cereal byproducts from the General Mills processing plants and the miscanthus has worked out really well.”

The biomass crop is grown on 1,500 acres, which provides about 10% of the university’s powerload.

“They pay farmers to grow it, so that’s $2 million in local farm revenue and the university is not spending money out of state on coal,” the university professor said.

Since plants are one of the best carbon removal technologies, Heaton said, farmers are the ones that can make money because they have the natural resources to capture carbon.

“Illinois is strategically positioned to grow stuff and we’re good at it,” she said.

In addition, Illinois has the opportunity to store carbon in geologic structures.

“Because of our geology we have these deep saline shelves where the salt water helps trap carbon dioxide in deep geologic formations,” Heaton said. “Because of this, Illinois has the largest number of active carbon capture and storage access points in the U.S. and ADM has been the leader in this technology.”

Illinois has an opportunity to make money in ways a lot of people can’t.

“Because carbon is a global economy, we can store it here and people from around the world will pay us,” Heaton said.

Growing miscanthus does not work for every farmer.

“I don’t think it should be on more than 10% of our cropland,” Heaton said. “It is not a wholesale replacement for anything we’re doing today, but it complements our corn-soybean and livestock systems nicely.”

In Iowa, poultry producers are using miscanthus as a replacement for wood chips to bed their poultry barns.

“Our pulp and paper industry has been declining in this country for decades, so there are less wood chips for bedding,” Heaton said.

“Poultry farmers are growing miscanthus and chopping it for bedding and they are getting improvements in broiler production with bigger, healthier birds that have healthier feet,” she said. “Then they take the spent bedding and turn it into renewable natural gas, so there are lots of different opportunities to make money.”

Additional markets that are developing for biomass crops include sustainable aviation fuel, building materials, kitty litter and packaging materials such as egg cartons.

Heaton discussed ways for farmers to integrate 10% perennial crops on tile-drained lands in a way that makes money and improves the farming operation.

One option is to grow miscanthus in potholes, which are places where water ponds in a field.

“We have places where it is swampy and the soil doesn’t drain very well,” Heaton said. “There are places where it was a lake bed thousands of years ago and we have reduced crop yield in these places.”

In 2019, researchers planted miscanthus in three potholes in a corn-soybean field in Iowa.

“The profitability of the potholes goes from nothing to about $800 per hectare, so if you do it right, we make money because we had been losing money on the corn and soybeans,” Heaton said.

The university sells the miscanthus to Tyson for turkey bedding.

“The university made $19,000 on the miscanthus they sold from the research plots to Tyson,” Heaton said. “It’s a small market now, but it’s developing.”