While most row crops have been harvested by now, there is still one crop standing on an increasing number of acres across Iowa. And the farmers growing it are looking to turn it into springtime cash.
This relatively new cash crop in Iowa, giant miscanthus grass (miscanthus × giganteus, or Mxg for short), has been grown in Europe and parts of the U.S. for many years and has the potential to deliver additional profitability to Iowa farms. In addition, it offers numerous environmental benefits.
The University of Iowa has promoted Mxg as part of its initiative to eliminate the use of coal for energy production by 2025. To this end, the university has engaged with farmers and commercial producers of Mxg to deliver the harvested grass for production of energy pellets as fuel for its power plant. According to the project website, 1 acre of Mxg can take the place of 4 tons of coal.
ISU associate professor and ISU Extension biomass expert, Emily Heaton, says Mxg is a hardy perennial crop that can be planted opportunistically in areas that are underperforming with traditional row crops. Once established, the plants require very little pesticide or nutrient application, and since the plant propagates through its slow-growing rhizome system instead of seed, there is little risk of it becoming a nuisance within the row crop plantings.
Perennial crop has advantages
Steve Schomberg has been growing Mxg for seven years on his farm near Letts in southeast Iowa. He has 48 acres in Mxg for the University of Iowa, and planted 15 acres for his own commercial ventures. He took on managing the farms he and his sisters own with the help of Hertz Farm Management after retiring from the University of Illinois in 2005, where he first learned of Mxg.
“I’ve had a lifelong interest in soil conservation that I learned from my parents, and when I was looking for an alternate cash crop, I saw that Mxg had the potential to augment income while helping with soil retention on my farm,” Schomberg says. “I hope to get 20 years out of this crop with only one disking to rejuvenate the plants. And while I’m still experimenting, effective nitrogen application is trending toward one-third the rate used on my corn crops.”
NEW USES: With uses ranging from poultry litter to a replacement for coal, miscanthus is providing new income for growers.
Schomberg has the 10- to 14-foot-tall, field-dried crop custom-cut with a silage chopper to leave about 18 inches. He then uses a flail mower to chop the remaining stalks and bales it for trial applications, including livestock bedding and erosion control.
The largest commercial Mxg producer in the U.S. is AGgrow in Greensboro, N.C. Its chief executive officer, Travis Hedrick, is looking to build multiple markets for this versatile crop.
“This is a new crop, so we must bring along the producers and the consumers hand in hand to build a viable and profitable marketplace,” Hedrick says. “We’ve developed technologies to bring it to market on a commercial scale and made investments in advanced genetics to improve future production. The University of Iowa project has been a great opportunity to establish Iowa production for a renewable energy project, but there are many other uses we are developing as well. We believe other markets can benefit from this sustainable fiber resource.”
Emerging commercial markets
Beyond power generation, two early commercial opportunities for Mxg rely on the excellent absorbency characteristics of the dried grass. Hedrick says his company sells poultry bedding and miscanthus fiber in seven states.
Livestock bedding for poultry, swine and cattle are key areas AGgrow is targeting. The company cites studies showing that the grass is three times more absorbent than alternative bedding products. In poultry barns, use has been shown to improve production through higher feed conversion and lower mortality. The grasses’ soft texture is also credited with improving animal welfare and improved foot pad scores.
Schomberg is working with livestock producers in Iowa to build momentum in the bedding market as well. He has provided baled Mxg cuttings to three livestock producers with cow-calf operations. He’s received positive feedback, with one going so far as to say they were amazed by the absorbency.
“I also heard high praise from an Iowa farmer who said, ‘It works!’ after using it in a trailer to haul fat cattle to market,” Schomberg says. “Another mentioned he would be using it in his calving shed after seeing that he could hardly tell calves had been in a holding pen where Mxg was used.”
Absorbency is the key characteristic in another commercial market where Mxg is taking hold. Sediment retention devices — commonly referred to as erosion socks — are used at construction sites and other areas to keep soil in place. In a comparative study, AGgrow Wattle devices demonstrated 95.7% soil retention effectiveness, outpacing the commonly used straw, compost or excelsior products by as much as 30%.
AGgrow’s Hedrick notes that the Mxg Wattle devices are much lighter and easier to work with during installation. And since the fiber is pH neutral and free of weed seed, they are friendly to the worksite ecosystem. He also says bales of Mxg are being used for erosion control (seeding cover) by commercial companies and government agencies.
With strong incumbent products already established in the bedding and erosion control markets, building demand for Mxg will take time and effort on the part of producers. Schomberg says it’s very early in the bedding market in Iowa and producers must recognize that Mxg will be a long-term business development process. “There is a market, but we still need to accelerate demand by building positive experiences among users to establish Mxg as a premium bedding or ‘super straw’ product,” he adds.
ISU’s Heaton consistently promotes the planting of perennial grasses such as Mxg as a way to reduce erosion and nutrient runoff from tilled fields. The dense underground structures help hold soil in place while steadily increasing biomass. Other benefits of the plants in the field include nutrient and carbon retention.
“Perennial grasses naturally use nitrogen and reduce leaching,” Heaton says. “Other environmental benefits from the plants include excellent carbon sequestration characteristics that can help offset greenhouse gas emissions elsewhere on the farm.”
A fundamental goal of the University of Iowa energy program is reduction of harmful emissions from its power plant. Mxg helps with this by supplanting coal for energy production and by “cleansing the air” of carbon.
AGgrow’s Hedrick reinforced the emissions benefit in a different phase of Mxg production when he stated that local production of Mxg for bedding and erosion control had the potential to significantly reduce transportation-related emissions. “The high absorbency of Mxg also reduces barn emissions and runoff, retaining nutrients that can be easily composted and returned to the soil to support crop growth,” Hedrick says.
There is also a wildlife habitat upside to growing Mxg. Perennial fields are not tilled and, therefore, support wildlife throughout the growing season. And, since the plants stand in the fields through the winter, they create natural shelter and habitat for many creatures. These increases in habitat can help improve biodiversity throughout the natural ecosystem.
Ripley is an Iowa Learning Farms conservation outreach specialist.