The Botany of Desire: A Plant's-Eye View of the World

by Michael Pollan

Forsline has devoted a career to preserving and expanding the apple’s genetic diversity. He’s convinced that the modern history of the apple—particularly the practice of growing a dwindling handful of cloned varieties in vast orchards—has rendered it less fit as a plant, which is one reason modern apples require more pesticide than any other food crop. Forsline explained why this is so. In the wild a plant and its pests are continually coevolving, in a dance of resistance and conquest that can have no ultimate victor. But coevolution ceases in an orchard of grafted trees, since they are genetically identical from generation to generation. The problem very simply is that the apple trees no longer reproduce sexually, as they do when they’re grown from seed, and sex is nature’s way of creating fresh genetic combinations. At the same time the viruses, bacteria, fungi, and insects keep very much at it, reproducing sexually and continuing to evolve until eventually they hit on the precise genetic combination that allows them to overcome whatever resistance the apples may have once possessed. Suddenly total victory is in the pests’ sight—unless, that is, people come to the tree’s rescue, wielding the tools of modern chemistry. Put another way, the domestication of the apple has gone too far, to the point where the species’ fitness for life in nature (where it still has to live, after all) has been dangerously compromised. Reduced to the handful of genetically identical clones tha...