Pioneering Perennials in Iowa Soil

The University of Iowa is searching for the right biomass feedstock to cofire with coal at its power plant, and miscanthus is one option a few early adopters are testing.
By Katie Fletcher | February 05, 2015

Crops take time to establish. Not only do proper planting and harvesting practices need instituting, but an end market must exist. Southeast-Asia originated Miscanthus × giganteus serves as one among a variety of energy crops studied in Iowa. Over the past few years, two miscanthus test plots have been planted in Iowa; 12 acres in the spring of 2013 in Muscatine County, and another 16 acres near Iowa City the following spring. Now with planting protocol explored at both sites, the initial harvest of the 2013 test plot is just around the corner. The harvested miscanthus will be one of several options cofired with coal in two solid-fuel boilers at the university, in an effort to reach its 40 percent renewable energy commitment by 2020. The university has provided the end market for the first two growers to participate in its biomass fuel project. Although preliminary efforts have revealed substantial data on miscanthus, more research and test runs must be done before outreach to a few early adopters turns into a mass-marketing effort.

Early Adopters
Growing miscanthus is not a pioneering operation everywhere. Europe has been planting the crop since the 1980s, primarily for combustion in power plants. In the continental U.S. South, farmers grow the perennial for a poultry-bedding end market. A few other states have grown miscanthus, but, overall, miscanthus is in its early stages in the U.S., and only a few early adopters have begun looking into incorporating it, and other perennials and grasslands, into farming operations.
 “I’m always looking to diversify our portfolio of crops,” says Steve Schomberg, the first grower participating in the biomass fuel project in 2013. “I think it has a great future, as a landowner and farmer you don’t want to put all of your eggs in one basket.”

This is perhaps why over coffee with a friend Schomberg’s ears perked up when he heard about UI’s project. Another Iowa grower followed in 2014. “The concept of growing fuel is pretty interesting,” says Dan Black, owner of the 2014 pilot plot.
These two growers knocked on the university’s door, and are now helping spread the word to others interested in leasing sections of land for the project’s purpose. “We want to have 2,500 acres in production to support our 2020 goal,” says Ferman Milster, principal engineer of renewables at UI.  “We’re going to be ramping up 200 acres this coming year, and then much more than that in the years to come.”

As a predominantly liberal arts and sciences school, UI turned to the agricultural expertise of Iowa State University for support. This is when Emily Heaton, assistant professor and extension biomass specialist at ISU, got involved. “It’s a fantastic partnership,” Heaton says. “Their university is taking the risk on transitioning their power plant, and Iowa State is taking the risk on understanding the agronomic implications of the crops they choose, trying to do all the testing for them at a research scale to understand what they should start implementing.”

Both universities work together with outreach and extension to Iowa growers. “We’ve been working since 2012 to answer questions they (UI) have, and the questions of their farmers, as well as getting the word out to farmers and getting more of the crop adopted in the Iowa City area,” Heaton says.

Growers and the universities are optimistic they will easily obtain more land for miscanthus. “There has been quite a bit of interest bottom line; everybody is very curious,” Black says.

“I’ve had quite a bit of interest—just roadside interest—the local guys talking to me about it,” Schomberg says.

Lessons Learned
All involved with the project work closely with one another through each step, but UI is bearing a majority of the risk. UI leases the land from both Schomberg and Black, and then turns around and hires them to manage the plot while it pays for the planting cost, field preparation, time and labor. “There is not a lot of risk for me on my side of this deal because they’ve taken on so much of the risk, and so much of the responsibility of getting the crop in,” Black says.

UI issued a request for proposals for the planting both years. In 2013, New Energy Farms was chosen, and in 2014 Repreve Renewables was selected. Miscanthus does not produce a harvestable yield during the first year of growth. Usually the first harvest occurs in late winter or early spring after the second growing season. Schomberg’s test plot was planted during adverse circumstances, but is scheduled to be harvested during that time frame based on snow cover and climate. “It was really a combination of the late planting, which stressed the rhizomes, and then the drought, which stressed them, and then the extremely long winter we had, which provided further stress,” Milster says. “Out of the planted acres, three acres did survive and look very good.”

Heaton expects the acreage to yield 8 to 10 tons per acre on average once the miscanthus is fully matured, which takes about three years. 

Heaton compares miscanthus to children; they are expensive to have, and the first few years of upbringing are critical. “We generally talk about miscanthus as being a very low-input crop, and that’s true especially when you look at it over a 20- to 30- year lifespan of the crop, but you don’t want to mess around in those first few years,” Heaton says. “It’s an expensive crop to plant, just like kids are expensive to have, so we do recommend diligent management in the first two years. Like children, if you do a poor job in its juvenile phase, it will never recover.”

Although miscanthus can flourish on marginal land, the soil needs proper preparation. Both primary and secondary tillage is needed to loosen the dirt enough to dig trenches for the rhizomes. “One of the secrets to a successful establishment, to effective planting, is field prep,” Milster says. “In both cases, we really had to put extra effort in to prepare the soil.”

Rhizome planting is based on potato planting. Black says the planter used by Repreve, in essence, has the bones of a potato planter, but is highly modified to plant the rhizomes.

When Miscanthus Makes Sense
Miscanthus must be carefully planted, but after it is established little upkeep is required. Heaton and others at ISU are working with farmers to understand when utilizing the benefits of miscanthus, prairie and other grasslands could make sense to a grower, not only environmentally, but also economically. “Our vision at Iowa State and the University of Iowa is to have a suite of perennials integrated into the crop landscape,” Heaton says. “The reason I would include miscanthus in a diversified crop portfolio in the Midwest is really pretty straightforward: its yield.”

Heaton and others at ISU are trying to identify at a subfield scale where a grower should integrate perennials, like miscanthus, to improve profitability of corn in Iowa. “I would like to see 15 percent of land in Iowa fields transitioned to perennials, and I’d like to see those perennials be a diverse portfolio,” Heaton says. “It wouldn’t take much miscanthus to make a meaningful difference to our energy needs in the state.”

Heaton says landscape management is analogous to healthcare, in a sense. Imagine if you could identify all the smokers in a population. Heaton asks, “Would you want to insure them at the same rate, with the same premiums that you are insuring a healthier portion of the population?”

Heaton, as many others posed that question, says probably not. “What we’re considering here is that we finally have data that allows us to ask the same question for parts of land,” Heaton says. “We don’t want to invest the same resources, either insurance resources from a taxpayer or actual farm input from a farmer, on areas of land that are not going to respond, not going to be profitable, not going to produce grain, etc.”

Miscanthus × giganteus, the sterile type of miscanthus UI and ISU are using, is an attractive option for a few reasons. It is unable to produce seed, so this helps to avoid unintended movement of the crop from planted areas. Further, the perennial can help manage poorly drained fields and underperforming areas. Miscanthus also helps mitigate soil and other nutrients from water. “Planting dedicated energy crops is the single, most-effective measure you can take to help with nutrient runoff,” Milster says.

This is why researchers believe miscanthus makes sense in poorly drained soils, and might be a good option to plant in lower corn suitability rating (CSR) ground where a grower would typically lose money planting other commodities. Schomberg says medium-fertility soils around 40 to 70 CSR is the range being considered for miscanthus.

Black and Schomberg believe growers interested in implementing miscanthus need to both understand and think about what the right conditions are for planting miscanthus. These test plots and subsequent research are helping reach that understanding.

Establishing End Market
“Anyone with the long-term investment in their land knows, they need to take care of certain portions of it differently than other portions, it is a no-brainer for them,” Heaton says. “The challenge has always been the economics, and that challenge still exists.”

One problem is the lack of a crop insurance program for miscanthus. “Banks don’t understand miscanthus, so getting a loan for those early years is difficult,” Heaton says.

As an extension biomass specialist, Heaton believes in the future her work could include helping banks understand the return schedule for perennial crops. Right now the federal government’s Biomass Crop Assistance Program recognizes these crops take time to mature, but not everyone can get BCAP subsidies, according to Heaton.

Programs like BCAP can help with developing markets. Milster believes miscanthus can be competitive on $5 a bushel corn, especially on marginal land, for UI’s end market. UI’s main power plant currently cofires oat hulls with coal in two boilers. The oat hulls come from a partnership with Quaker Oats in Cedar Rapids, Iowa. Other ready-to-burn biomass streams under consideration, along with miscanthus, are expired corn seeds, poplar wood chips, switchgrass and reed canary grass. The university calculated prices for these options at the power plant. The prices are calculated to give an energy cost of $5 MMBtu, which is comparable to current coal costs. Miscanthus grass calculations showed that at 10 percent moisture content, it would have a heat value of 7,200 Btu per pound, yielding $72 per ton at $5 MMBtu and 113,000 tons equal to the 2020 goal.

UI brings the market, removing the market risk. Other markets also exist or are emerging such as poultry bedding and feedstock for cellulosic ethanol production. “I think the markets will come, and hopefully we can get out there and establish a protocol for growing it, and best management practices for growing it that will be replicated as the market expands,” Milster says.

Since the university’s miscanthus market is in its early beginnings, “we want to work very closely with a small number of farmers to make sure every story is a success story,” Heaton says.

Schomberg and Black hope that in the near future with results from their test plots they can help establish where the opportunities lie in diversifying predominantly corn and soybean Iowa cropland. “Miscanthus, any new crop like this, will take a while to establish,” Schomberg says. “There will be early adopters, like we are, and then we’ll get experience, become more efficient, become more cost-efficient. We will learn from mistakes we make so we can help people that follow in our footsteps into a better job.”

Author: Katie Fletcher
Staff Writer, Biomass Magazine