The $65 billion crop is depleting aquifers, polluting the Gulf of Mexico, and contributing to climate change.

King Corn

Excerpted from an article by Todd Woody, TakePart’s senior editor for environment and wildlife.

Forget the military-industrial complex. Start worrying about the $65 billion corn-industrial complex.

The United States is the world’s biggest corn producer, with 36 percent of the global market—China is No. 2, with 22 percent—and corn is the nation’s biggest crop. How big? One-third of farmland in the U.S. is devoted to growing corn, which covers the equivalent of two Floridas. The top 45 companies that rely on corn as a crucial ingredient had revenues of $1.7 trillion in 2013, according to a report released Wednesday by Ceres, the Boston-based nonprofit that promotes corporate sustainability.

The extensive study by Ceres details the corn industry’s environmental impact, finding, for instance, that 87 percent of the irrigated corn crop is grown in water-stressed regions.

“Over half of the country’s irrigated corn production—worth nearly $9 billion annually—depends on groundwater from the over-exploited High Plains aquifer,” according to the report.

Farmers apply an immense amount of fertilizer to grow all that corn—9.5 million tons of nitrogen in 2010. “Nitrogen run-off from cornfields is the single largest source of nutrient pollution to the Gulf of Mexico’s ‘dead zone,’ an area the size of Connecticut that is essentially devoid of life due to agricultural run-off,” the reports states, citing U.S. government statistics.

So what is to be done? The report recommends that growers adopt better fertilization practices and switch to drip irrigation and other water-efficient technologies. (A fifth of corn is still grown by flooding furrows.)

The report’s best advice to corporate corn customers and investors, though, was this: “When possible, buy less corn.” That’s also true for consumers, who can lessen the demand for corn by scrutinizing product labels and avoiding processed foods.