Climate change doesn’t mean banana trees will replace corn stalks in the Midwest, but growing corn will likely become a greater challenge. And the Corn Belt will likely move northward.
“There’s a lot of stuff happening that affects how we grow crops,” says Richard Wolkowski, University of Wisconsin soil scientist emeritus. “We already see a lot more variability in our weather. We’re seeing more localized drought and heat stress, more intense rainstorms (elsewhere) with more potential for erosion. The average daily temperatures are going up, and the overnights lows are higher.”
This means Wisconsin growers will likely have an extended growing season and be able to plant higher yielding, higher relative maturity hybrids, adds Wolkowski. “The Midwest won’t become a desert, but it’ll be harder to farm to the norm,” he says, referring to average temperature, precipitation and growing days. “The key point is that farmers will have to become more nimble and prepared to adapt their practices.”
Jerry Hatfield, laboratory director of the USDA-ARS National Laboratory for Agriculture and the Environment, says on a scale of 1 to 10 (if 1 is not at all and 10 is apocalyptic) he’d peg the risks associated with climate change at a 6 or 7 for corn growers.
“The caveat that goes with that is it’s really going to depend on where they’re at. The biggest impact will be the increased variability in weather during a growing season,” says Hatfield.
The next five to 10 years is going to be a very uncertain time for farmers, he says.
“Farmers can prepare for a long-term gradual warming, but not for wild swings of the weather from season to season – or within a season,” he adds. “It’s hard to change the planting date in July.”
BUILD SOIL QUALITY
Maintaining soil quality or health is one of the best ways for to prepare this uncertain future, say Hatfield and Wolkowski. To preserve yields, water management during grain-fill will be critical. Proactive steps include adopting agronomic practices such as no-till or strip till, keeping residue on soils and using cover crops to rebuild soil organic matter and improve soil health. Other steps include maintaining waterways and improving residue management.
Genetics, environment and management practices determine yields, says Hatfield, who advises producers to concentrate on the factors within your control.
“They have a genetic resource,” he says, “and an environmental factor that they can’t control. They have management factors that are 100% in their control. Preparation is more than just selecting a drought-resistant variety.”
Hatfield says his research shows that out of a 100 units of moisture on bare soil, 40 units will evaporate. In no-till soils with residue cover, 20 units will be lost. Additionally, corn roots are nearer the surface in soils with residue cover, which allows the plant to take advantage of light rains. In dry soils, the roots are nowhere near the surface and light rainfall won’t reach the corn roots.
“The real pay-off for soil health is water,” he adds. “Case in point: This year good soils with good water storage got fantastic yields.”
Producers divided about climate change
Producers are more likely to believe that climate change is fueled by natural causes than human activities, according to the initial results of a multistate, multiyear project led by researchers at Iowa State University to assess producer attitudes toward climate change.
Among producers, two-thirds believe climate change is occurring, a belief that mirrors the general public, says J. Gordon Arbuckle Jr., ISU assistant professor of Sociology, who presented initial research results in October at the recent agronomist and crop/soil scientists annual meeting (ASA-CSSA-SSA).
“One difference is that farmers are more likely to believe that climate change is due more to natural causes than human actions,” he adds.
According to the survey of 5,000 growers in 11 states, 25% believe that climate change is occurring, and it is caused mostly by natural changes in the environment. Another 33% attribute the cause more or less equally to natural changes and human activities, and 8% believe climate change is due caused mostly by human activity. However, 4% say climate change isn't occurring and 31% say there isn't enough evidence to say with certainty that it is.
The survey also showed that while many farmers support individual-level adaptations and institutional action to mitigate the impact of climate change, producers are more supportive of individual or private sector action than state or federal mandates, Arbuckle says.
“Importantly, nearly half of farmers who don’t believe in climate change do support doing more to protect farmland from weather variability,” he says.
The next step in the research is to interview 200 producers one-on-one to better understand perspectives on adaptive and mitigative practices and ideas on how to turn concern into action.
“Those who believe in climate change are worried about what’s coming,” Arbuckle says.
According to the survey, the top five worries of farmers are:
1. Drought and heat
2. Excess water issues
3. Pest and disease issues
4. Nutrient loss
5. Soil erosion