The Omnivore's Dilemma - Michael Pollan [20]
One way to tell the story of this farm is by following the steady upward arc in the yield of corn. Naylor has no idea how many bushels of corn per acre his grandfather could produce, but the average back in 1920 was about twenty bushels per acre—roughly the same yields historically realized by Native Americans. Corn then was planted in widely spaced bunches in a checkerboard pattern so farmers could easily cultivate between the stands in either direction. Hybrid seed came on the market in the late the 1930s, when his father was farming. “You heard stories,” George shouted over the din of the tractor. “How they talked him into raising an acre or two of the new hybrid, and by god when the old corn fell over, the hybrid stood straight up. Doubled Dad’s yields, till he was getting seventy to eighty an acre in the fifties.” George has doubled that yet again, some years getting as much as two hundred bushels of corn per acre. The only other domesticated species ever to have multiplied its productivity by such a factor is the Holstein cow.
“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, Naylor explained. The higher yield of modern hybrids stems mainly from the fact that they can be planted so close together, thirty thousand to the acre instead of eight thousand in his father’s day. Planting the old open-pollinated (nonhybrid) varieties so densely would result in stalks grown spindly as they jostled each other for sunlight; eventually the plants would topple in the wind. Hybrids have been bred for thicker stalks and stronger root systems, the better to stand upright in a crowd and withstand mechanical harvesting. Basically, modern hybrids can tolerate the corn equivalent of city life, growing amid the multitudes without succumbing to urban stress.
You would think that competition among individuals would threaten the tranquility of such a crowded metropolis, yet the modern field of corn forms a most orderly mob. This is because every plant in it, being an F-1 hybrid, is genetically identical to every other. Since no individual plant has inherited any competitive edge over any other, precious resources like sunlight, water, and soil nutrients are shared equitably. There are no alpha corn plants to hog the light or fertilizer. The true socialist utopia turns out to be a field of F-1 hybrid plants.
Iowa begins to look a little different when you think of its sprawling fields as cities of corn, the land, in its own way, settled as densely as Manhattan for the very same purpose: to maximize real estate values. There may be little pavement out here, but this is no middle landscape. Though by any reasonable definition Iowa is a rural state, it is more thoroughly developed than many cities: A mere 2 percent of the state’s land remains what it used to be (tall-grass prairie), every square foot of the rest having been completely remade by man. The only thing missing from this man-made landscape is…man.
3. VANISHING SPECIES
A case can be made that the corn plant’s population explosion in places like Iowa is responsible for pushing out not only other plants but the animals and then finally the people, too. When Naylor’s grandfather arrived in America the population of Greene County was near its peak: 16,467 people. In the most recent census it had fallen to 10,366. There are many reasons for the depopulation of the American Farm Belt, but the triumph of corn deserves a large share of the blame—or the credit, depending on your point of view.
When George Naylor’s grandfather was farming, the typical Iowa farm was home to whole families of different plant and animal species, corn being only the fourth most common. Horses were the first, because every farm needed working animals (there were only 225 tractors in all of America in 1920), followed by cattle, chickens, and then corn. After corn came hogs, apples, hay, oats, potatoes, and cherries; many Iowa farms