AMES, Iowa – Farmers faced with tight profit margins may consider cutting back on weed control efforts this growing season, but an Iowa State University agronomist said doing so may cost farmers money in the long term.

Robert Hartzler, a professor of agronomy and ISU Extension and Outreach weed expert, said low commodity prices in recent years may lead farmers to tolerate a low population of weeds that might not affect yields.

But doing so may allow enough weeds to go to seed in fields and give rise to the spread of herbicide resistant weeds in the future, a growing concern for corn and soybean producers across the state.

“Farmers might be tempted to do just enough to protect yields but still allow some weeds to survive,” Hartzler said. “They might be unwilling to spend the extra money to get to the next level of weed control, and, in the short term, you can rationalize that. But in the long term, that’s going to lead to further evolution of resistance.”