John Oliver tackles the US corn industry: ‘You might be thinking, so what?’

John Oliver dug into the US corn industry on Last Week Tonight, from how the government subsidizes it, to its many uses and the effects of its dominance. The US is the world’s largest producer of corn, and produces more of it than any other crop. Farming it is a nearly $90bn industry; corn fields occupy nearly 90m acres a year, or about 5% of the land surface in the contiguous US.

“You might already be thinking, so what?” said Oliver. “That means that America is well-stocked for the movies, barbecues and house parties where someone wants that black bean salsa thing. Why do you have to ruin a good thing? To which I say: one, it’s a calling and a clarity of purpose. And two, of those millions of acres of corn, only 1% is made for direct human consumption.” The rest is called field or dent corn, which can be used for other products such as cornmeal, high-fructose corn syrup, paint and plastics.

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Such products only account for about 15% of US domestic corn use; 40% is used for animal feed, and 45% for fuel and the gasoline alternative ethanol. And “while corn is incredibly versatile, the way we’ve incentivized farming it has caused considerable downstream harm,” Oliver explained. “Because it turns out that corn’s utter dominance of American agriculture comes at the expense of our environment, our health, and some of our farming communities.”

The US, he noted, was naturally well-suited to grow corn, but government policy has contributed to the crop’s dominance by “heavily thumbing the scale in incentivizing what crops farmers choose to grow”. Starting in the 1970s, the Nixon administration encouraged expansion of farm operations, with the federal government paying the difference if the price fell below a certain threshold. The change in policy helped create almost immediate surpluses in commodity crops, especially corn.

Similar policies still exist today, with government subsidies for part of a farmer’s crop insurance. “While the subsidies sometimes get positioned as protections for small family farmers, the truth is that is not who reaps the vast majority of the benefits, which tend to flow to the biggest producers,” said Oliver. In the past 28 years, he noted, 79% of federal farm subsidies went to the top 10% of producers; meanwhile, the vast majority of farmers do not benefit from federal farm subsidy programs at all.

It’s more difficult for small farms, which are more likely to grow a diverse array of crops, to qualify for subsidies. And it’s very easy for people not directly involved in farming yet who are related to large producers to receive subsidies. “You could make similar criticisms of wheat or soybeans, but the biggest share of the subsidies in recent decades have gone to corn, far surpassing that of any other crop,” Oliver explained. “Basically, in the world of agricultural products, corn is the unquestionable superstar – beans want to be it, oats want to fuck it. And as the corn industry has ballooned, some of the biggest beneficiaries haven’t actually been the farmers themselves, but enormous corporations.”

The emphasis on corn has also had negative effects on the environment. Nitrogen fertilizer can cause serious birth defects and lead to “dead zones” of oceans devoid of oxygen in the water. And because it’s so cheap, corn is now the main ingredient for livestock feed, though they are not evolved to digest it.

“But maybe the most ridiculous way that we use corn is ethanol,” said Oliver. In an attempt to decrease US dependency on foreign oil, Congress passed the Energy Tax Act of 1978, which encouraged the use ethanol. Production further increased with a 2005 energy bill setting renewable fuel standards that mandated some renewable fuel had to be blended into the domestic gasoline supply. “Essentially, every gallon of domestic gasoline now legally has to have at least a little bit of ethanol in it, in the same way that every pop album currently has to have at least a little bit of Jack Antonoff in it,” said Oliver. “It’s just the law now.”

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That’s despite plenty of downsides to ethanol – namely that its promise of lowering greenhouse gas emissions doesn’t hold up. When factoring in the fertilizer and land use changes needed to grow the corn to produce it, corn ethanol produced under the renewable fuel standard has a carbon footprint at least 24% higher than regular gasoline. It has also pushed productions into areas of the country, such as Texas and western Kansas, without the groundwater reserves to support the crop.

Oliver recommended amending the renewable fuel standard, “because it makes no sense”, and resetting the US farm policy, such as making federal farm subsidies contingent on things like preserving topsoil, controlling runoff and slashing greenhouse gas emissions.

“The good news is, the Farm Bill is currently up for renewal, and we could do all of that,” he said. “The bad news is, as you have seen, there are powerful interests with no reason to want the status quo to change at all. But it just has to.”

Oliver assured that “this is not a takedown of corn,” and that he understood it was a national symbol of pride and a crucial source of jobs for many Americans. “But I do think that it is long past time that we shift our farming policy when it comes to America’s No 1 crop,” he concluded.