Polyculture fields resist pest outbreaks by hosting predator insects

Evidence

There were certainly bugs and weeds back when these valleys were Three Sisters gardens, and yet they flourished without insecticides. Polycultures—fields with many species of plants—are less susceptible to pest outbreaks than monocultures. The diversity of plant forms provides habitats for a wide array of insects. Some, like corn worms and bean beetles and squash borers, are there with the intent of feeding on the crop. But the diversity of plants also creates habitat for insects who eat the crop eaters. Predatory beetles and parasitic wasps coexist with the garden and keep the crop eaters under control. More than people are fed by this garden, but there is enough to go around. — Robin Wall Kimmerer, Braiding Sweetgrass, 486

Categorization

• XREF: Biodiversity-as-pest-control is the ecological mechanism behind the Three Sisters story — evidence for Grafting & Growth’s trees-as-infrastructure systems thinking. — connects to: Disturbance triggers insect outbreaks once populations cross a regulatory threshold — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1547; Monoculture management and fire exclusion promote insect-induced vegetation mortality — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1582; Frequent small animal disturbances maintain grassland diversity as a fine-grained mosaic — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 499 (+1 more)

Broader Connections

• Biodiversity protects systems from collapse while monocultures die wholesale under disease. #corroborates (0.85) — Rebecca A. Martusewicz, Jeff Edmundson, and John Lupinacci, EcoJustice Education, 1418
• Frequent small animal disturbances maintain grassland diversity as a fine-grained mosaic #expands (0.70) — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 499