|Dried-up corn field (Photo: Jolynne Martinez, Flickr)|
...In the case of corn, however, there are potentially trillions at stake because the industry now touches on almost every aspect of the American economy.
Corn production has doubled over the past 20 years and on its own was worth $65bn last year. But corn supplies a vast spread of industries. The 45 largest companies in the corn production chain together account for about $1.7tn in earnings, the report said.
Some 40% of the crop now goes for production of ethanol. Another 35% of the crop is grown for animal feed, but corn is used across the economy.
"It is fed to the cattle that become Big Mac. It is in the ethanol that goes into the gasoline we buy," Barton said. "It's in the snack foods that we buy, even in some of the plastics in the products we buy. It is in laundry detergents. It's everywhere."
But the crop carries a heavy environmental toll. Corn uses the most water for irrigation of any crop, and accounts for half of all fertilizer use.