A program approach to weed control — not any single pass or product — remains the most effective way to improve field results and mitigate herbicide-resistant weeds, according to Corteva Agriscience's Dr. Eric Scherder, U.S. Agronomy Leader for Herbicides and Nitrogen Stabilizers.

Scherder told Brownfield that the strategy is not new, but it consistently delivers better outcomes than relying on one application.

What does the program approach involve?

Scherder lays out a season-long framework built on sequential, complementary steps rather than a single rescue treatment:

• Start the season clean with burndown or residual herbicides before planting
• Scout fields regularly to catch escapes early
• Use multiple effective sites of action and layered residuals
• Follow through with timely post-emergence passes

The logic is straightforward. Weeds that emerge and set seed despite a single treatment are the ones most likely to carry resistance traits, and each escaped plant adds seed to the soil bank that growers will fight for multiple seasons.

Why resistance pressure keeps the strategy relevant

Weed resistance has spread across major U.S. row-crop regions for years, cutting into yield potential and raising herbicide costs per acre. Resistant waterhemp, Palmer amaranth and marestail populations force many growers to spend more on additional chemistry or tillage trips while still losing bushels at harvest.

A program approach addresses that pressure by attacking weeds at multiple points in their lifecycle, reducing the selection pressure that any single mode of action creates when used alone.

The bottom line for growers

Scherder's message is that discipline beats shortcuts. Growers who begin with clean fields, scout on a regular schedule and layer residuals through the season spend less on rescue treatments and protect yield better than those who depend on one high-profile herbicide pass.

As resistant weed populations continue to spread, Corteva's agronomy team expects the program approach to remain the standard recommendation for growers planning herbicide programs for coming seasons.