Soybean yields are rising roughly a bushel per year and corn about two bushels per year, and that steady genetic gain is pulling micronutrients out of soils faster than a generation ago, according to University of Illinois soil fertility specialist John Jones.

"We are running our soils at a faster rpm," Jones said, arguing that micronutrient removal and nutrient uptake are increasing over time as yields climb.

That shift reframes a familiar question for growers weighing marginal input spend. Micronutrient fertilizers were long treated as unnecessary: specialists a generation ago told farmers to fix soil pH first, noting that organic matter decomposition and impurities in traditional fertilizers and amendments typically supplied the small quantities crops required.

What has changed in the micronutrient equation?

Jones, in a recent conversation, said the framework still rests on several unchanging factors:

• Soil pH. If pH is off, micronutrient availability to the plant falls, and money spent on micronutrient fertilizer is largely wasted.
• Compaction. Unaddressed compaction can waste the same investment.
• Organic matter. Decomposition and impurities in fertilizer and amendments still deliver micronutrients to the soil profile.
• Erosion. Any loss of topsoil usually reduces nutrient availability.

What has changed is the yield side. Higher harvested bushels mean higher removal, and in theory a higher probability that micronutrient fertilizer nets a return. But Jones cautions that the payoff is field-specific, which makes one-size-fits-all prescriptions troublesome.

How should growers test micronutrient response?

Jones wants more on-farm research and says it does not need to be complicated.

"If you run a split planter, similar to how you might compare hybrids, and you see a consistent difference in that one-half of the planter versus the other, that's probably a good decision which would align with small-scale replicated research," Jones explained.

A consistent yield difference across strip trials could signal future payoff from a micronutrient investment. Before testing anything, growers should inventory what they already apply.

"Experiment with micros that have not yet been part of your program," Jones emphasized.

He pointed to zinc as an important consideration in corn and boron in crops such as alfalfa. Timing matters as much as product choice.

"The R2 growth stage in beans is just showing up to be very important," Jones said. "With that in mind, I would focus on looking at reproductive stage applications and evaluating those responses."

What about packages and risk management?

University research programs test micronutrients individually, but Jones said growers can reasonably experiment with commercial packages. Typical formulations include:

• Soybeans: manganese and zinc, with sulfur as a carrier molecule.
• Corn: manganese, zinc and boron, plus sulfur.

Discipline matters. Jones advised careful boron management to avoid toxicity issues. For iron deficiency chlorosis in soybeans, varietal selection and higher plant populations may prevent deficiency as effectively as any micronutrient purchase.

The bottom line for margins: verify pH, compaction and erosion first, because those factors determine whether a micronutrient dollar works at all. Then run split-planter strip trials on products never used before, timed to reproductive stages, before committing field-scale spend. As yields continue their bushel-per-year climb, Jones expects micronutrient demand to keep tightening, making replicated on-farm testing the cheapest way to find which micros pay.