Research Summary: "A minimum suite of soil health indicators for North American agriculture"

Bagnall, D. K., Rieke, E. L., Morgan, C. L. S., Liptzin, D. L., Cappellazzi, S. B., & Honeycutt, W. (2023). A minimum suite of soil health indicators for north american agriculture. Soil Security, 10 p.100084 https://doi.org/10.1016/j.soisec.2023.100084

In the paper entitled “A minimum suite of soil health indicators for North American agriculture”, the authors presented a need for effective soil health indicators to be identified so producers can accurately track how their management practices are affecting their soil’s health. To help fulfill this need, the authors tested 30 indicators across 124 long-term agricultural research sites in North America. Indicators were chosen if they reflected soil health, were responsive to management practices across North America, are applicable at scale, and do not measure the same thing a more direct indicator measures. These criteria were chosen to enable scaling of accurate indicators in a cost-effective way on a continental scale.

After filtering the 30 tested indicators through the four criteria points, the authors presented soil organic carbon, carbon mineralization after 24 hours, and aggregate stability as universal soil health indicators for use in North America. These indicators can give producers quantitative information on how their management practices are affecting soil health over time. If choosing to utilize these indicators, soil should be sampled during the same time of year under similar temperatures and moisture conditions. This is due to these factors causing changes in indicator values, particularly carbon mineralization. Furthermore, the same lab should be used each time samples are submitted as different labs can have variable results. If the same lab is not able to be used again, ensure that the new lab utilizes the same methods as the previous lab, otherwise the results will not be comparable. While costs will vary by locality and lab, running these three tests should cost approximately $50 per sample. If used correctly, these tests can give producers insight into how their practices affect soil health over time.