The trouble with this line of argument for backyard biodiversity, however, is that the heirloom open-pollinated varieties grown by home gardeners are hardly the last bastion of genetic diversity. In fact, they are not even a terribly significant one. The mistake of 1970 was not corrected by someone who had ordered Hopi Magenta Parch Corn from the Seeds of Change catalogue; it was corrected by those "agrichemical conglomerates" who have been systematically collecting and preserving samples of corn strains from all over the world on a huge scale. Tapping into their germ-plasm libraries, the companies were quickly able to develop new hybrids that eliminated the defective gene. Indeed, the very business of producing hybrids creates an enormous incentive for the discovery and preservation of what breeders usually term "landraces" -- traditional open-pollinated varieties.
William Niebur, the director of maize research for Pioneer Hi-Bred, the major producer of hybrid corn, says that "from a historical perspective every hybrid represents the crossing of, conservatively, twenty-five to seventy-five different genetic families." Pioneer maintains, in cold storage, seeds representing every original strain it has worked with since the 1920s; the company also carries out field tests of more than 100,000 new corn hybrids each year. The U.S. Department of Agriculture maintains a vast national germ-plasm bank as well. "If the genetic diversity is effectively maintained in the public or private sector on reserve, has it been lost?" Niebur asks.
In fact, rather than preserving diversity, replanting seed saved each year from open-pollinated varieties may result in a loss of old strains, since it will almost surely cause significant change owing to natural selection and random genetic "drift"; eventually the heirloom variety lovingly tended year after year will resemble its ancestor no more than a CD player resembles a Victrola. To insist that the only way to preserve traditional strains is to grow them in gardens is a bit like saying that the only way to preserve Model T Fords is to drive them to the store every day. Most people would think that keeping them in museums, where they can be conserved and studied, is as good an idea, if not a better one.
One recurring theme in modern environmentalism has been the tendency to take often trivial and intensely personal choices and elevate them to the status of global moral imperatives. I am not sure whether this tendency simply reflects misguided earnestness or indicates something deeper -- a wish to justify and give a sense of importance and high drama to the many trivial and intensely personal choices we make in our lives. But I am reasonably certain that when I wavered over a choice between the Crete Hybrid Muskmelon and the Jenny Lind Heirloom Melon as I filled out my seed order this winter, the world did not tremble.
Illustrations by Robert Zimmerman.
The Atlantic Monthly; June 1999; Politically Correct Planting - 99.06; Volume 283, No. 6; page 118-123.