Assessing how cover crops close the soil health gap in on‐farm experiments

Abstract

Assessing the success of cover crops (CCs) as a way to promote soil health at the farm scale remains a challenge. At four on‐farm CC experiments in Nebraska, we quantified soil health relative to a reference soil. We examined physical, chemical, and biological properties in near‐surface soil. Cover crops reduced the soil health gap between bare (no‐CC) and reference soil in the short (3‐yr) timescale, but the magnitude of responses depended on cropland management history and ecological dynamics of reference site plant communities. Increases in soil health relative to reference soils showed some relationship to increases in soybean [Glycine max (L.) Merr.] and corn (Zea mays L.) yields. Clear discrimination of reference from bare soils was most influenced by organic matter and infiltration measurements conducted under the highest sampling intensity. Framing soil metrics relative to reference soils and ensuring appropriate sampling intensity are important to quantify the effects of CC on farm landscapes.

An Integrated Framework for Reference Site Selection and Benchmarking Soil Health Studies in the United States

“…8). For instance, research by Krupek et al, (2022) illustrates how cover crops can narrow the soil health gap, tting into a higher hierarchical order compared to conventional practices. Similarly, Singh et al, (2023) demonstrate that conservation practices like no-till and cover crops are more effective than conventional methods, helping to close the gap with the reference state.…”

“…8). For instance, an initial target (T1) could be set to be reached with cover crops (Krupek et al, 2022) or manure management . Subsequently, a second target (T2) could be strategically set to advance beyond T1 by enhancing the existing management practices like cover crops and manure management and incorporating additional methods such as no-till farming (combining manure application with no-till techniques).…”

Corn response to long‐term seasonal weather stressors: A review

“…Other important research areas include the adoption of cover crops, when/if adopted properly, as potential strategies for drought mitigation. Cover crops can help by achieving better water infiltration levels (e.g., less water runoff) and better soil structure (Krupek et al., 2022) along with cooler temperatures in the soil (Yang et al., 2021a). Greater water productivity in the crop can be achieved if there is optimum water absorption in the soil and minimum water loss through soil evaporation or runoff.…”

Continuous Living Cover: Adaptive Strategies for Putting Regenerative Agriculture into Practice

“…It follows that large amounts of agricultural land in the Midwestern US are dedicated to cropping systems that grow only maize and soybean [Boryan et al, 2011; USDA National Agricultural Statistics Service Cropland Data Layer (USDA NASS CDL), 2021]. Utilizing over-wintering cover crops in these systems has been shown to reduce soil erosion and nitrate leaching (Kaspar et al, 2007(Kaspar et al, , 2012Chen et al, 2022), is associated with a reduction in crop insurance losses due to drought, excess heat, and excess moisture (Aglasan and Rejesus, 2021), and possibly offer numerous other context-specific benefits such as increased soil infiltration rates, higher soil water-holding capacity, or increased soil organic matter content (Moore et al, 2014;Krupek et al, 2022;Nichols et al, 2022). However, the Midwestern maize-soybean systems present challenges to cover crop adoption.…”