Two decades ago, a summer drive along Dakota roads could take you by fields of color: the light green of wheat or oats, the purple of blooming flax, or the bright yellow of sunflower fields. Today, eastern Dakota fields are almost always two shades of green, the same colors that have been the palette of Iowa and Illinois for decades: the deep green of soybeans, or more commonly, the yellow-topped rich green of corn.
Here’s a look at what’s happening with Zea mays, this crop that now makes up so much of the Dakota landscape.
Why do we grow so much corn in the United States?
Corn is relatively easy to grow.
Corn has an inherent advantage as a plant: Few plants can create as many calories from a given amount of sunlight, water and basic elements. Native Americans recognized and nurtured these characteristics in corn, which gave it added genetic diversity to grow in a variety of conditions. Colonists arriving from Europe saw the benefits as well. In fact, some historians argue that if settlers had not taken on the growing of corn, they would not have been able to build a powerful nation in the New World.
Today, growing two crops such as corn and soybeans is easier than the half-a-dozen crops plus livestock that farmers used to have in their operations in the Dakotas, according to Chris Laingen, assistant professor of geography at Eastern Illinois University. He and his colleague from EIU, geographer and climatologist Cameron Craig, recently traveled through the Dakotas.
“I met with a farmer up by Tulare,” Laingen said. “It was a joke, but he pointed at the side of his truck and asked if I knew what 4×4 stood for. He said, ‘I work four weeks in the spring and four weeks in the fall.’ He plants his field, applies his chemicals. He might have to out there a couple more times, but in the fall he harvests it and that’s about it.”
Corn is versatile.
The push to continue to increase production of corn is in part due to all of the things that we have figured out we can make out of corn, Laingen said.
Corn makes up a substantial part of the American diet, and corn on the cob is a minor part of it. According to author Michael Pollan, of the approximately 45,000 items in an average supermarket, more than a quarter are in some way derived from corn: The corn fed to the livestock that ends up in the meat department, the corn-based sweeteners in beverages and many other foods, the modified corn starch used to hold foods like chicken nuggets together, the glucose fermented to create alcohol in beer, and much more.
It’s not surprising, then, that Americans’ bodies are in large part made up of corn. Todd Dawson, a scientist from the University of California-Berkeley, can test human hair and find out how much of the carbon in it came from corn. For one CNN correspondent who had his hair tested, 69 percent of that carbon was corn-based. “(W)e North Americans look like corn chips with legs,” Dawson says in Pollan’s 2007 book The Omnivore’s Dilemma.
Corn is also used in many nonfood items, such as disposable diapers, batteries, matches and magazines. It can also be used to make plastics.
“Ethanol was a big game-changer, too,” Laingen said. About 5.05 billion bushels of corn were used to make ethanol in 2011, which was more than was used for animal feed (about 5 billion) and far more than was used for human consumption (about 2.5 billion), according to the Scientific American. Laingen thinks, however, that we’ve now hit a saturation point in the amount of corn used for ethanol.
Policies have supported corn production.
- After World War II, great amounts of ammonium nitrate were left over from making munitions for the war effort. Agronomists at the U.S. Department of Agriculture lobbied to have them applied to farm fields, which increased yields and also kick-started the chemical fertilizer industry.
- U.S. Secretary of Agriculture Earl Butz’s call to increase production for the export market in the 1970s also played a role in increased corn production.
- Corn is the most highly subsidized crop. It received $3.5 billion in federal money in 2010, according to The New York Times.
- Ethanol has received much government support in recent decades, including a tax credit for blenders of gasoline. A mandate that these blenders use ethanol in gasoline was allowed to expire last year, but the tax credit still provides an incentive for ethanol’s use in gasoline blends.
Corn is easy to transport.
In addition to its versatility, corn is also can be exported and shipped easily, and “it doesn’t have has many issues with storage as small grains do,” Laingen said.
Much of the growth in corn production now will be sent to Asia, where an increase in population and a change toward more American-style eating mean corn is in demand. South Dakota Wheat Growers—which may want to consider a name change in the near future, since it now deals much more in corn than in wheat—has invested millions in its Connecting to Tomorrow project, which is designed “to reach global markets more efficiently and with higher volumes,” according to the Wheat Growers website.
Corn yields have increased dramatically.
Between 1939 and 2010, average U.S. corn yields increased six-fold, to a high of 165 bushels per acre. This increase was in large part due to the introduction of hybrid seeds and the increased use of nitrogen fertilizers.
One example a genetic improvement in corn varieties: Cornfields are much more crowded than they were a few years ago. Researchers have neared the natural limit on how many kernels can be grown per ear and how many ears can be grown per plant, but they have still been able to increase yield by creating varieties that are more tolerant of the stress of being very closely spaced in the field.
Are there problems with growing this much corn?
A massive corn harvest does have some negative side effects. Some examples:
- Corn requires a great deal of nitrogen. When corn is grown exclusively, it can deplete the soil, which then requires more nitrogen fertilizer to be added. Fertilizer runoff can contaminate groundwater.
- The abundance of corn is a double-edged sword for the U.S. diet. Food is cheap—even with price increases since 2008, no civilized nation spends less of its income on food, according to Michael Pollan—but much of the food in which corn is an ingredient is high in calories and low in nutrients. Moreover, studies have shown that when extra calories are around, we tend to eat them, so too many cheap calories can add to our obesity epidemic.
- The increased demand and high price for corn has led to the loss of grassland as farmers bring more and more land, most of which was previously considered unsuitable for cropland, into crop production. The loss of grassland is detrimental to wildlife of all kinds, but especially to grassland nesting birds. A lot of the land being brought into crop production had been left as pasture before because it was steep, sandy, wet or had some other limitation. As this land is converted to cropland, it is highly prone to erosion and other problems.
- The favorable economics of corn production have also pushed aside other crops. As farmers grow more corn and less of other things, their crop rotations get shorter or disappear altogether. This loss of diversity has a negative impact on soil health and also makes crops more susceptible to an outbreak of insects or disease.
What do we mean by the “Corn Belt”?
1927 – Agricultural geographer O.E. Baker drew a rough outline of the Corn Belt in 1927, shown in the dark orange area on this map. He described the Corn Belt as a region “in which corn is produced in great quantities and is more important than any other crop.” This region included only the southernmost Dakotafire counties: Sanborn, Miller, and parts of Jerauld, Beadle and Kingsbury. Most Dakotafire counties were in the “Spring Wheat Region.”
1950 – The U.S. Department of Agriculture did a more precise map of the Corn Belt based on county lines. The Corn Belt now included several South Dakota counties just outside of the James River Valley that hadn’t been in Baker’s 1927 version: Roberts, Grant, Codington and Hamlin.
How has the Corn Belt changed?
In 1986, John Fraser Hart, who studied the rural landscapes of the United States, noted that “The Corn Belt is in turmoil. Its traditional system of mixed farming, which had flourished for almost 150 years, has been replaced since World War II by highly specialized types of agriculture.” He was looking at the 1950 USDA borders of the Corn Belt when he made that statement; now, Laingen and Craig find, that change has spread with the Corn Belt into all Dakotafire counties in North and South Dakota, and even farther north than that.
What will happen in the Corn Belt next?
Laingen is tracking the march of corn northwest, into regions that did not have a long enough season to grow it until recently.
“There is a convergence of technology allowing corn to be grown up there when it couldn’t have in the past just because of how long it took corn to mature,” Laingen said.
He and Craig took a drive through corn-growing country in preparation for future work demarcating how far the Corn Belt has spread. Their tour resulted in an article entitled “Another Notch in the Corn Belt,” which was published last summer in Focus on Geography.
According to Laingen and Craig, “Two themes that we heard and saw evidence of time and time again were 1) increased production and 2) the phrase ‘we’re going to grow what makes the most economic sense.’”
What makes the most sense in Dakotafire counties now is apparently corn. Corn is now grown well past the 1950 outline of the Corn Belt, into all Dakotafire counties and beyond (though some North Dakota counties grow more soybeans than corn).
Nationally, U.S. farmers are planting the largest corn crop in 75 years. If the weather cooperates, the U.S. could produce 48 million tons of corn this year, up 4.5 million tons from last year. This could lower corn prices significantly, but even so, the overall “economic sense” of corn is unlikely to be affected.