Planting the city of corn

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"High yield" is a fairly abstract concept, and I wondered what it meant at the level of the plant: more cobs per stalk? More kernels per cob? Neither of the above, the farmer explained. The higher yield of modern hybrids stems mainly from the fact that they can be planted so close together, 30 thousand to the acre instead of 8 thousand in his father's day. (...) Basically, modern hybrids can tolerate the corn equivalent of city life, growing amid the multitudes without succumbing to urban stress.

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The great turning point in the modern history of corn, which in turn marks a key turning point in the industrialization of our food, can be dated with some precision to the day in 1947 when the huge munitions plant at Muscle Shoals, Alabama, switched over to making chemical fertilizer. After the war the government had found itself with a tremendous surplus of ammonium nitrate, the principal ingredient in the making of explosives. Ammonium nitrate also happens to be an excellent source of nitrogen for plants. serious thought was given to spraying America's forests with the surplus chemical, to help out the timber industry. But agronomists in the Department of Agriculture had a better idea: spread the ammonium nitrate on farmland as fertilizer. The chemical fertilizer industry (along with that of pesticides, which are based on poison gases developed for the war) is the product of the government's effort to convert its war machine to peacetime purposes. As the Indian farmer activist Vandana Shiva says in her speeches, "we're still eating the leftovers of World War II".

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Of all the species that figured out how to thrive in a world dominated by Homo sapiens, surely no other has succeeded more spectacularly - has colonized more acres and bodies - than Zea mays, the grass that domesticated its domesticator.

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in The Omnivore's Dilemma