Sustainability Defined

In this, the second of a three part series on the potential of corn, Vital looks at sustainability from an agriculture perspective. But it’s more than just the grower’s hand that contributes to environmental improvements — seed companies and equipment manufacturers play a large role in developing a solution.

Corn growers are seizing solutions to make sustainability more economical. Once, low-technology and low-yield production were the only image of sustainable agriculture. Now, new transgenic seeds coupled with innovative equipment choices will unlock the potential of today’s corn plants while preserving land for future global fuel, food and feed needs.


Ask 10 farmers and you’ll get 20 answers. That’s how Bob Johnson describes the difficulty in defining sustainable agriculture. He and his extended family grow 1,650 acres of corn and 500 acres of soybeans, while also running a farrow-to-finish operation near DeKalb, Ill. He said that while sustainability is an interesting term, and one that a lot of groups are grabbing hold of, like most things related to farming, in the end it has to come down to “economics, and not just agronomics, over the long term.”

The United States Department of Agriculture (USDA) defines “sustainable” agriculture as farming systems that are “capable of maintaining their productivity and usefulness to society indefinitely. Such systems… must be resource-conserving, socially supportive, commercially competitive and environmentally sound.”

That’s a tall order. To meet it, growers are using a variety of methods – greater implementation of conservation tillage, advanced chemical and trait technologies in corn and use of equipment specifically designed to handle these practices.


To reduce the carbon loss from soil and prevent erosion, growers are leaving more crop residue cover on the field and making greater use of conservation tillage practices.

But leaving soil undisturbed to allow carbon to accumulate is only part of the story. Conservation tillage practices can also reduce CO2-related emissions from farm machinery. And for farmers following these practices, there’s also the potential to reduce labor costs, enhance soil fertility, improve water management and erosion control and reduce intensive pest management.

Depending on the type of land, previous crops and several other factors, methods of conservation tillage are varied.

In no till, soil is left undisturbed from harvest to planting except for nutrient injection. Planting is done in a narrow seedbed or slot.

Ridge till is similar, but the seedbed is prepared on ridges with residue left between ridges. Strip till involves preparing seedbeds in strips and alternating crops.

Some growers utilize mulch till which leaves soil undisturbed until just prior to planting.

The continued shift toward no-till corn production could have significant impact on reducing the amount of CO2 released in corn production. Some researchers believe no-till practices create a carbon sink, meaning more carbon is taken up by the soil than is released to the air in corn production. Measurable results vary by region and are impacted by climate and other factors, but according to results of the Indiana Carbon Storage Project, no-till on Indiana cropland can store five times more carbon than conventional tillage.

Conservation tillage and the USDA Conservation Reserve Program, which encourages marginal land to be taken out of production, have reduced soil erosion by 1 billion tons per year, according to a recent study released by the Conservation Tillage Information Center. That’s a 30 percent reduction since the early 1980s when traditional plowing methods were more common.

Reduced use of chemical fertilizer applications is another goal of sustainable growers. Livestock manure provides valuable nutrient content, particularly in nitrogen and phosphorus, while adding organic matter and often improving water-holding capacity of the soil.

“We raise a fair amount of hogs, so the majority of our fertilizer comes from manure,” Johnson relates. “Manure has become a valuable resource in the last two to three years. It used to just be something we had to get rid of.”

He utilizes variable rate technology for any commercial fertilizer used. “We try not to put on nutrients that aren’t needed,” he adds.


While conservation tillage practices will continue to be essential, in recent years biotechnology advances have provided additional avenues for sustainability.

Syngenta, an international seed and crop protection company with a biotechnology headquarters in the U.S., keeps a persistent focus on sustainability.

“We’re positioned to help growers take advantage of a number of possible ways to increase the sustainability of their operations,” said Steve Eury, Communications Manager at Syngenta. He said the company recently set up a dedicated sustainability group to look at specific pilot programs for growers in a number of crops.

Promising technologies in agronomy include new seed treatments that protect emerging plants, biotech traits to control a wide spectrum of pests, drought tolerance and nitrogen utilization traits and new chemistries capable of reducing plant stress.

“Through the use of technology and by employing best agronomic practices, corn producers will continue to significantly increase yield and to do it in ever-more sustainable ways,” Eury said.


Rob Zemenchik, Marketing Manager of tillage products for Case IH North America, Racine, Wisconsin, sees both trends — greater use of conservation tillage and adoption of biotechnology — as interacting to shape equipment innovations for current and future corn production.

One of the changes he sees is a transformation in the chemical composition of the corn plant itself in some transgenic hybrids.

“Following corn harvest, more crop residue mass is expected with higher yields. What is less well known is that the amount of lignin content in the corn stover can be 18 to 28 percent greater, which makes it tougher. Together, this means growers have to manage crop residues differently than in the past. We have to be more aggressive in cutting and incorporating residue into the soil while maintaining a suitable mulch cover to protect precious soil resources.”

With more farmers recently turning to corn planted on corn rotations in order to participate in the burgeoning biofuel industry, there is even less time for corn stalks to break down between crops. Importantly, year to year crop residue mass will fluctuate with rainfall patterns, interacting with key crop inputs, together making crop residue cycling strategies less routine than in the past.

“All of this affects machine design,” Zemenchik explains. “Growers need the capacity to handle tough, heavy corn residues, but have the ability to adjust to other crops in the rotation, such as soybean and wheat. Many prior machine designs will struggle to meet these challenges. If corn grain yield continues to rise at 1-2 bushels per acre per year as it has for most of the current generation of farmers, we can expect the increased residues also. For corn, increasingly large, sturdy leaves and stems fill potentially large ears with sugars in a source-to-sink relationship. Add to that, today’s farmers place more seeds per acre than previously, giving rise to overall yield increases and more residue biomass.”

To incorporate these trends Case IH has recently introduced the all-new Ecolotiger-870 (Fall, deep, aggressive) and the True-Tandem 330 Turbo (Fall and/or Spring, shallow, fast) – both equipped to handle the crop residue volumes in this new paradigm. These machines have undergone many years of testing development and are now available to growers to meet these challenges.

Utilizing transgenic seed to reach sustainable cropping goals can be effective, but tillage practices, and equipment engineered specifically for these practices, have to also be a part of the equation, he said.


Sustainable agriculture is not only a priority here in the United States but in other regions as well. In its May 2009 Global Impact Study, consulting group PG Economics Ltd. estimates that about 13.3 million farmers in 25 countries are using agricultural biotechnology to some degree. Less fuel is used and more carbon is returned to the soil with transgenic hybrids that allow for reduced tillage. In 2007, this benefit alone was equivalent to removing 14.2 billion kg of carbon dioxide from the atmosphere or the same as removing nearly 6.3 million cars from the road in one year.

Further, reduction in the need for pesticide spraying has meant that global environmental impact associated with herbicide and insecticide use in areas planted with biotech crops is estimated to have declined by about 17.2 percent.


Contrary to once-common belief, sustainability does not have to come at the expense of economics. The global impact study from PG Economics Ltd. concludes that use of biotech crops has meant farm income gains in 2007 equivalent to adding 4.4 percent to the value of global production of soybeans, corn, canola and cotton. Nearly half that benefit — or about $20.5 billion — was due to yield gains with the balance realized through lowered costs of production.

“It is possible to develop sustainable farming and produce enough crops to fulfill the demands for food, feed and glucose for fermentation products,” Thomas Videbaek, Executive Vice President for Novozymes A/S, Bagsvaerd, Denmark said, adding that sustainable agriculture is also important in addressing issues like global warming.

Both economical and environmental advantages can be garnered from hybrids developed to more effectively use soil nutrients, reducing fertilizer needs, Videbaek adds. But high yields will continue to be an overriding goal. He is optimistic over expected developments in that area over the next 10 to 20 years.

Even so, minimizing corn’s carbon footprint while still maximizing yield and profits is no easy task. But Matt Liebman, Professor of Agronomy and H.A. Wallace Chair for Sustainable Agriculture at Iowa State University, Ames, said it doesn’t have to be an insurmountable one.

“Sustainable systems need to meet multiple goals, including environmental, economic and food sufficiency,” he explains. “If a system doesn’t seek to maximize just one aspect, but rather to optimize including, multiple goals, then you are talking about a big challenge.”

And meeting that challenge shouldn’t end with the farm field. Sustainable systems, said Liebman, should ideally include jobs in the community and other economic factors that contribute greatly to production agriculture’s ability to enhance the quality of rural life.

“Many of these parts of the system are typically not valued in the same way that bushels per acre are,” he admits. “We don’t have a marketplace that compensates farmers adequately.” And that can be a problem for growers who are making greater investments to assure sustainable outcomes.

“I think farmers need a portfolio of revenue sources. Carbon credits can’t do it all. They are one stream of revenue,” Liebman said. “We also need to compensate farmers for maintaining soil condition, water quality and wildlife habitat.”

Frank Moore agrees that carbon credits are not the only answer to rewarding sustainable practices. After participating with other farmers from his region the past few years in a carbon credit program, the Cresco, Iowa, corn farmer expects benefits of the program to dwindle under current economic conditions. But that won’t deter him from sustainable practices.

Moore admits he’s probably not typical of farmers in his area. All of his 1,700 acres are farmed no till, which he’s been doing for the last 20 years and any opportunity to safeguard water and soil is a priority. “We’re also trying a lot of new technologies,” he said.

Moore makes diligent use of soil tests and variable rate fertilizer applications. While he admits to trying a lot of new sustainable practices, he’s quick to add that he also monitors the economics every step of the way with agricultural management software.

“I can see my profit and loss. It’s been a real eye opener. Bottom line is, I own less equipment but I can farm more acres because it takes less time,” he explains.

Next on his list? He’d like to look into ways to do some corn-on-corn rotations and experiment more with strip till.


Liebman said he’s seeing more and more farmers like Moore who want to alter their cropping systems as the demand for biofuels grows and adds that it’s especially important to maximize soil cover in such cases.

“It’s also important to realize you will need adequate amounts of nitrogen,” said Liebman. “Inputs become greater when you go corn after corn.” And although careful management can improve outcomes, he said growers can see decreases in yields in corn on corn situations, relative to corn on soybean.

But greater corn channeled for ethanol use has also spurred biotechnologies that improve yield along with agriculture sustainability. Syngenta’s Eury points out that biotechnology can have a direct impact on biofuel production, just like any technology that contributes to greater yield.

“Preliminary studies suggest significant economic gains and through-put for an ethanol plant and have demonstrated that the carbon footprint of corn-to-ethanol can be reduced by 10 percent or more from the use of the product and good crop management practices,” he said. He characterizes such advancements as involving companies, biofuels producers and growers in three-way partnerships to produce, manage and use emerging technologies.

That’s a message that hits home in the Heartland.

“Corn growers rightly see the emergence of biofuels as another potential source of value and we believe their role is critical because the most obvious way to achieve the renewable fuels mandate set by the government is by innovating within the existing infrastructure and practices,” adds Eury.

“We believe growers have been preparing themselves for this for decades by enthusiastically adopting technology that has led to improvements in yield and sustainability year after year and by looking to get more and more value from their crop. In the future, we believe growers will need to be seen not just as suppliers of a raw commodity, but as partners who will increasingly supply a high-value specialty ingredient.”




Vital is a news & media resource published by POET, presenting a variety of stories with the thought leadership one expects from the largest, most forward-thinking bioethanol producer.