Real-world decisions have real-world consequences.

That’s why Iowa State University (ISU) entomologist Erin Hodgson and her colleagues remain firm in their recommendation not to spray for pests like soybean aphids unless populations have reached economic injury levels, even though she knows in reality farmers often “throw in” an insecticide when they’re applying fungicides.

She understands the economics. “Why not? It’s cheap,” Hodgson shrugged during a back-and-forth discussion with farmers and agronomists at the ISU Integrated Crop Management Conference. Adding an insecticide to knock out aphids only costs a couple dollars per acre, saving the time and cost of another trip across the ...