Soybean Conservation Research Explores Tillage and Cover Crop Practices

Recent field research in Illinois and Iowa has examined how different conservation farming practices affect soybean yields and soil health. The studies were initiated following dust storms in the Midwest, including a fatal event near Springfield in May 2023.

Trials took place in 2024 and 2025 at six locations across central Illinois and north-central Iowa. Researchers evaluated soybean performance under four management systems: conventional tillage, fall strip-tillage, no-tillage, and no-tillage with a cereal rye cover crop. Each system was paired with three starter fertilizer strategies, including no starter, 15 pounds of nitrogen per acre, and 15 pounds of nitrogen with 10 pounds of sulfur per acre.

At the Iowa sites, grain yield was the primary measurement, while the Illinois sites included detailed observations of plant and soil characteristics throughout the growing season. The research aimed to provide data on how conservation practices influence both crop output and soil conditions.

Separate long-term research in southern Illinois, spanning 50 years, found that soybean yields were higher when conservation tillage was used compared to conventional tillage. The same long-term study reported that corn yields did not show differences based on tillage method, but no-tillage improved soil structure in poorly drained soils over several decades.

What the numbers show

• Field trials were conducted at six sites in 2024 and 2025
• Cover cropping could improve yields on 45% of cropland globally
• No-tillage was found to benefit 37% of cropland in a global assessment
• Organic farming could improve yields on 5% of cropland, according to a global study

Global assessments have provided additional context for these findings. One review found that cover cropping could improve yields on about 45% of cropland, with agroforestry and no-tillage also showing positive effects on 41% and 37% of cropland, respectively. Organic farming was identified as beneficial for yield improvement on 5% of cropland area.

Another meta-analysis, which included data from 179 croplands worldwide, indicated that landscapes with half of the area managed organically could optimize crop yields, biodiversity, and overall agricultural multifunctionality without necessarily reducing yields.

The combination of regional field trials and global research contributes to a broader understanding of how conservation practices can affect both productivity and environmental outcomes. These studies provide data for farmers and policymakers considering changes to tillage and cover crop strategies.

Ongoing research continues to gather information on the long-term impacts of conservation systems, with a focus on yield stability and soil health across different environments and management approaches.

* This article is based on publicly available information at the time of writing.