In southern Minnesota, fields full of corn and soybeans hold plenty of potential. With fertile soil and adequate moisture, farmers here fare well, most years.
Gregg Johnson, though, concerns himself with the marginal parts of these fields—the areas that often don't yield well, that fail to give a good return on the money invested in inputs.
"How do you arrange things on the landscape as new markets emerge and not interfere with the bread and butter crops, the corn and soybeans? I want to find crops that don't necessarily compete for land but take advantage of those areas where corn and beans don't grow so well,” explains Johnson, a research agronomist at the University of Minnesota's Southern Research and Outreach Center in Waseca.
In research plots, Johnson plants trees—willows and poplars—that are aimed at biomass and bioenergy markets. "The buzzword is multifunctionality. Can we get two, three or even four products and hedge our economics? The whole concept of what we're doing is based on space,” he says.
Johnson shows off his plots like a proud producer displaying his new calf crop. He grows willow for three years before cutting. The poplar stays longer; some have been here eight years. The willow, grown on twin 30" rows with 5' middles, grows back after chopping.
"With willow, we think you're looking at a 25- or 30-year crop. Nobody has worked with it for 30 years, so we don't know,” he says.
"Pheasant grows best with some open areas and some cover. The cover should not be so high that a hawk predator can look around from up top. Staggered planting keeps willow and poplar in the juvenile stage—dense from a biomass standpoint but not so dense the birds can't run around underneath or fly out of it,” Johnson says.
Johnson collaborates with scientists at the State University of New York (SUNY). Tom Volk, a researcher with the College of Environmental Science and Forestry on SUNY's Syracuse campus, has worked with willow since 1986. "Our goal when we started was to develop a biomass crop for marginal, poorly drained land,” Volk says.
SUNY now works with willow trials in Michigan, Wisconsin, Vermont, Delaware, Maryland and, in Canada, Alberta and Prince Edward Island. The college is also trying to develop willow varieties specifically for the Midwest. Some New York farmers are now trying willow, hoping to snag newly developing biomass markets.
"It's a chicken-and-egg challenge as far as marketing goes. It takes three years to get a crop off. But things are looking good,” Volk says. A specially designed New Holland forage chopper promises to simplify willow harvest.
Willow wood chips could provide feedstock for cellulosic ethanol plants, Volk says, as well as offset supply fluctuations for wood-fired power plants. Catalyst Renewables LLC uses patented SUNY willow varieties at Lyonsdale Biomass, a 19-megawatt wood powered electricity and thermal energy generating plant in Lyons Falls, N.Y. Middlebury College in Vermont began testing willow this year at a biomass plant to heat its campus, contracting with local farmers to grow it.
Johnson says developing reliable markets is key to the project's ultimate success. "We've got to convince growers to grow it and to wait three years before they get anything. What incentives are there to commit a farmer without assurance of a market on the other end?” he asks.
Johnson looks at the less productive parts of fields in the area and understands that trees for biomass could potentially make money for Minnesota farmers. "If we can plant perennial crops in areas that have potential for soil erosion or nitrate and phosphorus loss, it will help farmers and help on water-quality issues,” he says.
You can e-mail Charles Johnson at
- December 2008