Corn’s Clean-Energy Promise Is Clashing with Its Climate Footprint

by Ames Alexander (Floodlight/Wisconsin Examiner) ... The fertilizer used to grow it is warming the planet and contaminating water. Corn is essential to the rural economy and to the world’s food supply, and researchers say the problem isn’t the corn itself. It’s how we grow it.

Corn farmers rely on heavy fertilizer use to sustain today’s high yields. And when that nitrogen breaks down in the soil, it releases nitrous oxide, a greenhouse gas nearly 300 times more potent than carbon dioxide. Producing nitrogen fertilizer also emits large amounts of carbon dioxide, adding to its climate footprint.

Agriculture accounts for more than 10% of U.S. greenhouse gas emissions, and corn uses more than two-thirds of all nitrogen fertilizer nationwide — making it the leading driver of agricultural nitrous oxide emissions, studies show.

Researchers say proven conservation steps — such as planting rows of trees, shrubs and grasses in corn fields — could sharply reduce these emissions. But the Trump administration has eliminated many of the incentives that helped farmers try such practices.

Experts say it all raises a larger question: If America’s most widely planted crop is worsening climate change, shouldn’t we begin growing it a different way?

The same analysis estimates that in 2022, farmers applied more than 16 million pounds of nitrogen beyond what crops needed, sending runoff into wells, streams and other water systems.

What cleaner corn could look like

Reducing corn’s climate footprint is possible — but the farmers trying to do it are swimming against the policy tide.

And in April, Trump’s USDA canceled the $3 billion Partnerships for Climate-Smart Commodities initiative, a grant program designed to promote farming and forestry practices to improve soil and reduce greenhouse gas emissions. The agency said that the program’s administrative costs meant too little money was reaching farmers, while Agriculture Secretary Brooke Rollins dismissed it as part of the “green new scam.”

University of Iowa professor Silvia Secchi said the rollback of the Climate-Smart program has already given farmers “cold feet” about adopting conservation practices. “The impact of this has been devastating,” said Secchi, a natural resources economist who teaches at the university’s School of Earth, Environment and Sustainability.

Research shows what’s possible if farmers had support. In its recent report, the Environmental Working Group found that four proven conservation practices — including planting trees, shrubs and hedgerows in corn fields — could make a measurable difference.

Implementing those practices on just 4% of continuous corn acres across Illinois, Iowa, Minnesota and Wisconsin would cut total greenhouse gas emissions by the equivalent of taking more than 850,000 gasoline cars off the road, EWG found.

Despite setbacks at the federal level, some farmers are already showing what a more climate-friendly Corn Belt could look like.

In northern Iowa, Wendy Johnson farms 1,200 acres of corn and soybeans with her father. On 130 of those acres, she’s trying something different: She’s planting fruit and nut trees, organic grains, shrubs and other plants that need little or no nitrogen fertilizer.

“The more perennials we can have on the ground, the better it is for the climate,” she said.

Across the rest of the farm, they enrich the soil by rotating crops and planting cover crops. They’ve also converted less productive parts of the fields into “prairie strips” — bands of prairie grass that store carbon and require no fertilizer.

Under the now-cancelled Climate-Smart grant program, they were supposed to receive technical assistance and about $20,000 a year to expand those practices. The grant program was terminated before they got any of the money.

“It’s hard to take risks on your own,” Johnson said. “That’s where federal support really helps. Because agriculture is a high-risk occupation.”

In southeast Iowa, sixth-generation farmer Levi Lyle, who mixes organic and conventional methods across 290 acres, uses a three-year rotation, extensive cover crops and a technique called roller-crimping — flattening rye each spring to create a mulch that suppresses weeds, feeds the soil and reduces fertilizer needs.

“The roller crimping of cover crops is a huge, huge opportunity to sequester more carbon, improve soil health, save money on chemicals and still get a similar yield,” he said.

But farmers get few government incentives to take such climate-friendly steps, Lyle said. “There is a lack of seriousness about supporting farmers to implement these new practices,” he said.

And without federal programs to offset the risk, the innovations that Lyle and Johnson are trying remain exceptions — not the norm.

Many farmers still see prairie strips or patches of trees as a waste, said Luke Gran, whose company helps Iowa farmers establish perennials.

“My eyes do not lie,” Gran said. “I have not seen extensive change to cover cropping or tillage across the broad acreage of this state that I love.” READ MORE