Simplicity is one of the great virtues of healthy food. Yet out on the vast landscapes of industrial agriculture, where designer seeds sprout into processed commodities, simplicity is confounding nature, shifting bug demographics and leading to ever greater concentrations of chemical use.
Two recent studies involving researchers from the Kellogg Biological Station underscore the problem. The first, published in the journal Proceedings of the National Academy of Sciences, discovered that agricultural land in the U.S. Midwest is becoming less diverse with each passing year. That sets in motion a downward ecological spiral, according to Tim Meehan, a University of Wisconsin (Madison) entomologist who participated in the study.
“Two things drive this pattern,” he explained to the National Science Foundation. “As you remove natural habitats, you remove habitat for beneficial predatory insects, and when you create more cropland you make a bigger target for pests — giving them what they need to survive and multiply.”
Ongoing simplification in the American agricultural heartland is prompting substantial increases in pesticide use, according to the study. The National Science Foundation report observed: “One striking finding was that landscape simplification was associated with annual insecticide application to an additional 5,400 square miles — an area the size of Connecticut.”
The solution is a familiar one: Restore the natural balance. Kellogg researcher Doug Landis, a Michigan State University entomologist, advises farm owners to offset their immense monoculture fields by adding the diversity of native perennials, some of which could even be used to generate bioenergy: “Perennial crops provide year-round habitat for beneficial insects, birds, and other wildlife, and are critical for buffering streams and rivers from soil erosion and preventing nutrient and pesticide pollution.”
In our next post we’ll review the second study, which independently confirms one of nature’s great truths: Plant diversity matters.