Every farming operation is looking to control costs in 2026, with herbicides an obvious place to start. Madisen Carnes, an agricultural economics major and senior at Purdue University, has been studying herbicide programs with Assistant Professor Chad Fiechter. She said the challenge is that not every acre on a farm will respond the same way to cutting back on herbicides. It’s vital to know what types of soil conditions you have on every acre, and offered Indiana as an example.
“In northern Indiana, we see heavier soils, and in a lot of cases, a longer history of facing water hemp pressure. Herbicide programs in Northern Indiana are more aggressive, relying heavily on herbicide residuals and multiple modes of action. Resistance, especially to glyphosate, is already part of the equation. Up there, you can’t afford to fall behind early. In Central Indiana, it’s more variable. The soils are some of the most productive in the state, but here, consistent corn-soybean rotations have led to long-term herbicide use. Atrazine is still doing a lot of the work in some areas, and there’s a little more flexibility. In Southern Indiana, it’s a different challenge entirely. Soils are often lighter, more variable, and warmer conditions with longer growing seasons mean extended emergence windows and more late-season pressure. programs in the southern part of the state often rely on residuals that last longer to maintain control,
When deciding on whether to cut back on a herbicide program, Carnes said farmers should know what the cost of failure would be if it doesn’t work.
“Because if you cut back too much, you may save money up front, but you risk yield loss. You increase future pressure, and control gets more expensive with time. Lower-cost programs can end up costing more in the long run. Another economic factor is consistency. Programs that rely heavily on a single-post pass are more sensitive to timing and more vulnerable to weather delays, whereas strong residual programs buy you time, give you flexibility, and reduce execution risk.”
Weed resistance is another big factor to consider in potential herbicide cutbacks.
“Across Indiana, farmers are adapting to resistance. Where pressure is lower, herbicide programs can stay simpler. As resistance increases, we see more modes of action, more layering, and higher overall investment, because maintaining control requires it. So, when you pull all this together, a few things stand out. Residuals are doing most of the heavy lifting. Layering is what creates consistency. Geography drives how aggressive you need to be, and the goal isn’t to minimize costs. It’s to manage risk and protect return. The best programs aren’t built around one product or one pass, they’re built as systems, layered, preventative, and matched to the pressure you’re managing.”