Replacement crops for corn and soybeans may be on the way, but in the meantime, climate, plant genetics and infrastructure determine what, and how much, Iowa produces in its many farm fields. 

By optimizing Iowa’s farmland, global trade thrives and consumers get the most when they want it, according to Iowa State economists and agronomists. 

“The current genetics that we have, it would be very difficult to be able to make major switches to crops right now,” said Bobby Martens, associate professor in economics. “Now, could you raise some other crops? You could raise them, but it doesn’t come close to generating the revenue per acre that corn and beans do.”

Martens also said global markets can cause prices to fluctuate over the coming years. 

Genetic improvements have allowed corn and soybeans to thrive in Iowa, and a similar scientific change would need to occur to change crops, according to Martens. 

“As climate change continues to happen, maybe we could see other crops become really important for the state of Iowa,” Martens said. “If things really change we could be raising a fair amount of wheat here one day, but we would probably need some genetic improvements to be able to do that.” 

Mindy DeVries-Gelder, assistant teaching professor in agronomy, said the most realistic alternative crop might be wheat, though it would not be produced at as high of quality as other states, like North Dakota, might produce it. 

She also listed tomatoes, strawberries, sweet corn and popcorn as crops that are grown in Iowa and fit annual harvest rotations. 

DeVries-Gelder highlighted researchers at Iowa State who are researching more uses for mung beans, especially serving as a meat alternative, and millets because they are gluten-free. 

Mung beans have been grown in Asia for hundreds of years but are now being introduced in the Midwest to diversify land management and improve farm income, according to the Iowa State College of Agriculture and Life Sciences. The bean is used as a source of protein in vegetarian burgers, some kinds of pasta and cheeses. 

Proso millet, a cereal grain requiring less water than corn, is grown with no nitrogen fertilizer and is harvested using the same equipment as corn or soybeans. According to the College of Agriculture and Life Sciences, millet can substitute for most uses of corn, including ethanol and animal feed. 

Gary Munkvold, professor in plant pathology/entomology/microbiology, stated in an email response that soil fertility and adequate rainfall allow for some possible alternatives such as sorghum, small grains like wheat and barley, many types of oilseed and biofuel crops, as well as fruits and vegetables. 

An obstacle facing those alternatives’ viability and profitability is lack of disease resistance.

“Improved genetic resistance to fungal and bacterial diseases would help make these crops more profitable here,” Munkvold stated. 

“Another issue can be quality,” Munkvold stated. “For example, barley for malting has strict requirements for grain composition, which are difficult to meet growing in Iowa’s humid climate with current varieties. Breeding barley malting varieties that are better adapted to Iowa conditions would potentially open up a valuable opportunity for Iowa farmers.”

Yield improvements, especially corn, have kept up with the rising cost of production, according to Munkvold. 

The factors and advancements that brought corn and soybeans to where they are today are the same factors that need further addressed for the future of production, genetic resistance and environmental management.  

“Genetic resistance to common diseases and pests has simplified management in the field,” Munkvold stated. “Transgenic traits for insect resistance have made corn production easier, more efficient, and actually increased the safety of the grain for consumption. Transgenic traits for herbicide tolerance have also increased production efficiency and lowered costs. Like all genetic resistance traits, these are tools that have to be carefully used, and that has not always happened.”

Barriers

The lack of a developed market for alternative crops like sorghum, wheat and barley also can prevent large quantities from being produced in Iowa. 

“This is a self-reinforcing cycle; because the grain market has adapted to the predominance of corn/soybean production, the production system has become locked into feeding the existing marketing infrastructure,” Munkvold stated. “Some other crops like fruits and vegetables require much more labor (more expensive to grow) and the markets aren’t big enough to plant on the scale of corn and soybean.”

Inertia may stop farmers from switching away from the two staple commodities, according to DeVries-Gelder.

“Once I know how to grow something and do well at it and I can make it profitable and I’m doing that, it’s hard to change. Or, if you’re a new grower it’s really hard to come and do something that is very different than the rest of the system,” DeVries-Gelder said.

There are barriers to switching crops, too, according to DeVries-Gelder. 

One of the primary struggles would be the new infrastructure needed to accommodate new crops, which is currently set up to accommodate corn and soybeans. Infrastructure includes aspects of production such as storage and combines and other equipment needed to plant, harvest and distribute a new product. 

Markets, year-round desirability and crop insurance options may also deter farmers from producing crops outside of the two main commodities. 

“We are used to having access to what we want when we want it,” said Chad Hart, professor in economics. “When you think about food production systems, they don’t fit that.” 

Hart said although Iowa produces one round of crops per year, consumers still expect to see all products on grocery store shelves no matter what time of the year they shop, especially fruits and vegetables. 

By focusing on comparative advantages, land can be used to its full potential to trade for a high value for products best made elsewhere, Hart said. 

“Global trade is basically a way to connect those folks because…not everybody has access to the same soil,” Hart said. “[The green spots on the inserted map] have those soils that can produce those large crops; they concentrate on that. Those other areas concentrate on whatever they do best,” including labor, technology or tourism. 

DeVries-Gelder said Iowa farmers would face more variability if they planted crops such as tomatoes.

“We couldn’t compete in production with like the central valley of California, as far as when you think about how much we could produce and where. We would have some issues with the timing of our rainfall and our temperatures, that some years it would work really well, no different than my garden,” DeVries-Gelder said.

Instead, Iowa farmers aim to produce more stable crops that fit the climate at high yields and trade for other products Iowa farmers can not grow as heartily. 

Munkvold stated more frequent droughts and severe weather can damage crops, which leads to increased disease and pest pressure. Soil erosion is another factor in the future of farming. 

“Soil erosion is deteriorating the fertility and quality of Iowa soils and is not adequately being addressed,” Munkvold stated. “This increases input costs and potentially reduces return on investment, not to mention the environmental costs.”

The story of corn and soybeans coming about are different, according to Munkvold. Corn has been around longer than soybeans as a predominant crop, with soybeans gaining popularity when farmers needed a rotation crop to be grown on large acreages. 

The factors leading to corn and soybeans’ longevity as prominent crops have to do with labor, storage and land fertility. 

“Other factors include the fact that production of these crops has been highly mechanized, so the labor needs are minimal, and the crops are easily stored for relatively long periods,” Munkvold stated. “Other crops like vegetables are more difficult to store and transport while keeping them in good condition. Iowa has excellent soil fertility and topography (relatively flat) for growing crops on large acreages, lower land costs compared to the eastern states, adequate rainfall (usually) compared to the western states and lower disease and pest pressure compared to other parts of the U.S. such as the south.”