MCT via Getty Images A stunted field in Kansas, where drought and brutally high temperatures are killing the corn crop

Triple-digit days. Weeks with little to no rain. Soil crumbling away. Stunted corn stalks. Right now the fertile fields of the U.S. Midwest are experiencing corn-killing weather, with parts of five corn-growing states in the region experiencing severe or extreme drought. In at least nine states, one-fifth to one-half of cornfields are currently in poor or very poor conditions. And all of this comes after earlier expectations that corn farmers were going to produce a bumper crop this season, with 40 million hectares planted — the largest corn area in 75 years. Instead, we could see that crops wilt, as Darrel L. Good — a professor emeritus of agricultural and consumer economics at the University of Illinois at Urbana-Champaign — told the New York Times:

What we know is this: there’s been some permanent and substantive yield reduction already, and we’re on the cusp, depending on the weather, of taking that down quite a bit more.

(MORE: The Weather Really Is Getting Weirder)

So terrible is the weather in the heartland that farmers have begun to compare it to the drought of 1988, which wiped out millions of hectares of corn and caused $78 billion in crop damage, or even worse, the great Dust Bowl era of the 1930s. Already, stockpiles of corn have fallen by 48% from March to June, the biggest drop since 1996 — and that was before the drought and the brutally hot weather began in earnest. The percentage of the corn crop with top-quality ratings was 48% as of July 1, compared with 69% a year ago.

Whether 2012 goes down as just an off year for corn crops or a truly historic disaster will depend on the next couple of weeks. The pollination phase is imminent for corn plants in much of the country. That’s the period when ears of kernel-filled corn should be appearing on the plants. But drought and extreme heat can wither and stress corn plants, stunting their growth — or even preventing pollination altogether.

So far the summer of 2012 is still a long way from the terrible Dust Bowl conditions that remade American agriculture and resulted in an immense internal migration in the U.S., with Okies and the like heading west. Irrigation is far more common now than it was in the 1930s, and many farmers have drought insurance and other economic policies that will protect them — and keep them farming — in the event of a catastrophe. But the terrible heat toasting the Midwest this summer — 107ºF (42ºC) in Evansville, Ind. — is likely just a coming attraction for the extreme weather we’ll see in the near future, thanks to global warming. One of the most important questions scientists are trying to answer is just what impact the higher temperatures and drier weather, caused by climate change, will have on agriculture in America’s breadbasket. If the corn crop withers this summer, consider it a bad sign for the hotter days to come.

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