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

by Michael Pollan

I began to understand that organic farming was a lot more complicated than simply substituting good inputs for bad. A whole different metaphor seemed to be involved. Instead of buying many inputs at all, Heath relies on a long and complex crop rotation to avoid a buildup of crop-specific pests. He’s found, for instance, that planting wheat in a field prior to potatoes “confuses” the potato beetles when they emerge from their larval stage. He also plants strips of flowering plants on the margins of his potato fields—peas or alfalfa, usually—to attract the beneficial insects that dine on beetle larvae and aphids. If there aren’t enough beneficial insects around to do the job, he’ll introduce ladybugs. Heath also grows a dozen different varieties of potatoes, on the theory that biodiversity in a field, as in the wild, is the best defense against nature’s inevitable surprises.