Corn, Factory Farming and the Global Economy

The United States' most important crop, corn, is grown on a massive scale. The size of the crop influences environmental health, the country's food system and diet and what fuels the nation's automobiles. This series explores corn's role in contributing to factory farmed meat and obesity, how little of the crop gets directly eaten by people and how corn got so big in the US.

Little of the corn grown in the United States feeds the American people: much of it goes to creating ethanol and is also a large component of animal feed in confined animal feeding operations (CAFOs). The US is the largest exporter of the grain and helps determine corn prices worldwide.

Feed for Cows, Pigs and Chickens

Corn is more than food for people; it is used as feed for livestock and poultry. About 95 percent of feed grain production in the US consists of corn, and about a third of the US's total corn crop is used for animal feed. The USDA estimates there are 450,000 animal feeding operations in the US. 

In the US, corn has always been the go-to grain for animal feed. In fact, in the early days of American corn farming, so-called "invisible corn" in the form of hog feed led to other colloquial terms for pigs as "corn on the hoof" or "cornfields with legs." With the rise of concentrated animal feeding operations (CAFOs) and with feed cost as a big budget item, corn is a staple, and cheap, ingredient. The rise in corn over the last two centuries is a result of an indigenous crop that has high yields per input, a variety of uses, ability to be stored and improved technology for planting and harvest. Due to its importance, it has become the subject of national interest, receiving a preferred status in US agriculture policy. At the end of the 19th century, corn became a primary ingredient in feeding the massive stockyards in places like Chicago and Omaha. 

Beef cattle on feedlots usually consume a mixture of corn, roughage and other grains with the ratio determined by economics (i.e., corn and other feed prices) and how close the steer is to market. On dairy operations, cows will similarly be fed roughage, corn and other grains. Factory farmed hogs are fed corn and soybeans and chickens eat a corn blend.

As ethanol production ramped up capacity in response to the renewable fuel standard, distillers dried grains with solubles (DDGS), a co-product of the corn-to-ethanol operation, became economically-valuable and can be fed to cattle, hogs and chickens. For every bushel (56 pounds) of corn used in ethanol production, about 17 pounds of DDGS is produced.

Corn Exports

With 90 million acres (140,000 sq. mi., or the size of Colorado and New York combined) of land planted with corn, the US usually has enough corn to meet domestic demand and still have enough to export. The US typically exports less than 15 percent of the country's corn crop, yet still remains the world's largest exporter of the grain by volume. The dominance of the US export market means that the price of corn within the country usually sets the global price for the commodity. Since most of the Corn Belt (especially Iowa and Illinois) in the Midwestern US still relies on rain to water the crop, bad weather, including droughts and floods, can affect the size of the corn crop. Thus, a bad growing season in Iowa and Illinois could result in high corn commodity prices across the globe.

US corn exports began to rise in the 1970s. Through that decade, exports rose from 13 million metric tons to 62 million metric tons. Economic trouble, government price supports and the rise of the European Union caused exports to shrink to 31 million metric tons by the mid-eighties. By the 1990s, however, corn supplies rose because reduced government subsidies brought in more competitive pricing. These economic conditions allowed exports to increase to the 60 million metric ton range. Since the fall of communism and the rise of China as an economic powerhouse, corn exports have been volatile, but generally ranged in 40-50 million metric tons. Most of the corn grain that is exported is used for animal feed in countries that are expanding meat production.

US corn exports to Mexico under the North American Free Trade Agreement (NAFTA) had a dramatic effect on Mexican corn farmers. In 1994, NAFTA was signed, with one of the results (among many) that Mexico began importing US corn, displacing its own farms. One study reported that the number of corn farmers in Mexico fell from 10.7 million in 1991 to 8.6 million in 2007, despite the Mexican government subsidizing them with direct cash payments totaling $20 billion since 1994. Some of the two million farm workers that lost their livelihoods most likely began migrating north to the US looking for work, in some cases, emptying entire towns. Mexico continues to both import and grow its own corn, notably the white variety used for human food products. But increases in yellow corn imports are supporting increased meat production in Mexico.

America's Breadbasket

Only about seven percent of the US corn crop is used to feed the American people. Animals, exports and fuel tanks are the primary destination for the billions of bushels of corn produced every year primarily in the Corn Belt. American policy also encourages annual corn crops through insurance and commodity programs, export and food aid programs and the renewable fuel standard for ethanol. Corn is one of the most important American commodities that manifests very visibly on Midwestern farms and less visibly as the meat, dairy products and processed foods common on the American dinner table.


Image "Corn" by (Mick Baker)rooster on Flickr used under an  Attribution-NoDerivs 2.0 Generic license.