It’s natural for growers who are adopting regenerative agriculture practices to desire improvement in soil health as soon as possible. But researchers at the Univ. of Illinois say just as yield increases sometimes take years to see after adopting new practices, so do test results for soil metabolism.

Soil scientist Andrew Margenot says a recent 2-year mid-point appraisal of a 4-year Illinois-based project exploring soil respiration tests as indicators of soil health so far present a mixed bag of results.

Margenot, who directs the university’s soils lab and leads a research team of more than 40 students and other researchers, explains plot work at 2 sites in rich, deep northern Illinois soils — and also in what he calls “timber soils” in the southern region not affected by historic glaciation — shows it likely takes more than 2 years for lab results to show significant soil health changes.

The study, done in collaboration with the Illinois Soybean Assn., involves comparisons of tillage vs. no-till and cereal rye cover crops, or no cover crop, on plots in a corn-soybean rotation, corn double-cropped, and wheat, and soybean. 

The Illinois test sites are located near Monmouth in the northwest, near UI campus in east-central, and near Carbondale in the south. The northern-most sites…