For decades, Michigan State University Extension agricultural educators and specialists have urged farmers, gardeners and others who grow plants to test their soil. A properly collected soil test should be submitted with correct information about intended crop, yield goal, previous crop history, planned manure application, tillage depth and any other relevant information. MSU recommends that the sample should represent an area of similar soil characteristics and management not to exceed 20 acres per sample. The MSU Soil and Plant Nutrient Laboratory is an excellent place to have agricultural soil analyzed. Many other reputable commercial and university labs are also available.

Regardless of the strong arguments in favor of soil testing, including fine-tuned fertilizer use, protecting water resources from fertilizer runoff or leaching of excess nutrients, and potential improvement of plant performance and crop yield, many farmers choose not to soil test. At the same time we are urging farmers to use conventional soil testing procedures, new concepts and techniques are emerging to determine and understand soil fertility and health.

These new ideas were discussed at a planning session of MSU specialists, educators and AgBioResearch staff at the MSU Upper Peninsula Research and Extension Center in Chatham, Mich. The group met in May 2013 to discuss development of a major new research initiative at the center with a focus on soil health as impacted by crop and livestock management. With assistance from Jill Clapperton, soil health consultant with Rhizoterra, Inc., the group explored different ways soil health can be measured. Basically, these ways fall into three categories: chemical, physical and biological

  • Chemical. “Routine” soil analysis as described above, but including micronutrient analysis. Also, the Haney soil test, which includes organic and inorganic nutrients.
  • Physical. Water stable aggregates, porosity, infiltration, CAT scans/MRI.
  • Biological. Microbial activity: Respiration measurement (Solvita test), Phospholipid fatty acid (PLFA) analysis to understand the makeup of the soil microbe community, 16S ribosomal RNA analysis to identify bacterial strains present in soil. Soil fauna: Earthworm numbers and diversity, modified Berlese funnel to identify and count arthropods and nematodes.

By analyzing microbial components in soil, a more precise understanding of available nutrients can be gained and fertilizer recommendations adjusted accordingly. Soil health measurement procedures, including routine analysis including micronutrients and the Haney test, have been initiated at Chatham, Mich. Seventy samples have been collected representing about 1 acre each for the new research project area. Biological soil information will be collected on an annual basis.

The goal is to gain understanding and provide practical suggestions to producers regarding the potential for soil health improvements. We hope that these improvements will ultimately contribute to improved profitability for Michigan farmers and more sustainable agricultural systems.

Contact Jim Isleib, MSU Upper Peninsula crop production educator, at isleibj@anr.msu.edu or 906-387-2530.