Prairie Strips Show Fast Soil Health Improvements Across Crop Fields

By Andi Anderson

New research from Iowa State University scientists, conducted with the Soil Health Institute, shows that prairie strips can improve soil health much faster than previously expected.

Prairie strips are 30–100-foot-wide sections of perennial plants placed within crop fields to bring back some of the environmental benefits of native prairie while still allowing farmers to grow crops on most of their land.

Earlier studies found that establishing prairie strips on about 10% of a field could increase biodiversity, provide pollinator habitat, reduce erosion, and improve water quality. Until now, their effects on soil health were not well understood.

The new study, published in the Journal of Soil and Water Conservation, found that prairie strips improved eight of 12 measured soil health indicators within 10–12 years.

The greatest improvements were recorded in soil aggregate stability, microbial biomass, soil organic matter, and maximum water-holding capacity.

As researcher Marshall McDaniel explained, “It was an exciting surprise to see the degree of these changes over just a decade or so. It has been thought that it would take much longer to see some of these levels of change. Especially soil organic matter and maximum water-holding capacity.”

The study used a "paired chronoscope" approach, comparing 15 cropland areas with and without prairie strips, representing several Iowa landforms. Measurements focused on the top six inches of soil.

Additional in-depth analysis took place at the Neal Smith National Wildlife Refuge, where the oldest strip, established 12 years ago, was evaluated by Soil Health Institute scientist Elizabeth Riecke.

Broader findings from related studies led by Cole Dutter showed that microbial community changes extended far beyond the strips themselves. These changes increased nutrient cycling enzymes and improved soil moisture and plant-available nutrients more than three feet into the cropland without reducing yields.

Researchers noted that some farmers may consider rotating their strips to spread benefits across fields. As Lisa Schulte Moore shared, “Cole has initiated some interesting research looking at this idea. It is showing some long-term boosts to soil health and crop yields from rotating strips within fields.”

The team also highlighted simple DIY soil health tests, including aggregate stability assessments using the free Slakes app and water-holding capacity tests using a funnel and coffee filter, making soil monitoring accessible for farmers.

Photo Credit: gettyimages-sasiistock