Building soil organic matter on Upper Peninsula crop rotations – Part 1 of 2
Though not widely practiced, no-till cropping systems have potential on some Upper Peninsula farms.
All of the buzz about soil health – benefits for crop production, how to improve it, how to measure it – has left some Michigan farmers wondering where they fit into the discussion. Two main practices stand out front and center in the soil health discussion: no-till or reduced tillage planting systems, and inclusion of cover crops into rotations. Many of Michigan’s Upper Peninsula farmers are somewhat skeptical about the practical application of these techniques in their cropping systems because of short growing seasons and the widespread conviction that no-till “doesn’t work up here.” To simplify the issue, a focus on soil organic matter content may be helpful.
In February 2015, 57 Upper Peninsula farmers and agriculture industry people attended Michigan State University Extension cover crop educational meetings held in four Upper Peninsula locations: Rudyard, Chatham, Hancock and Escanaba, Michigan. Many of these farmers were primarily livestock producers with main crops of hay, pastures and occasional small grains. Feedback from attendees indicated farmers are interested in improving their soils, but feel that currently promoted practices focus on annual crop rotations and don’t apply to their systems. After all, when your rotation includes perhaps nine years of perennial forage and one year with a small grain including a new hay seeding, you are cover cropping as much as you could possibly be, right? And won’t that long-lasting perennial hay or pasture result in a maximum of soil organic matter accumulation?
Don’t we have some information about the results of no-till practices under Upper Peninsula conditions? Well, yes we do, but not from a controlled research project. Soil organic matter tests have been collected occasionally at the MSU Upper Peninsula Research and Extension Center. This was not done as part of a research project, but rather in the course of normal feed production for the Center’s cattle. The following MSU soil test report information is interesting. Keep in mind this is not a research project, just typical farm information:
- No-till management started in 1991.
- Typical rotation included corn, small grain, alfalfa.
- Soil organic matter levels were not measured until 1998.
- Average organic matter of 19 fields in no-till rotation tested in 1998 was 3.3 percent.
- Average organic matter of 16 fields in no-till rotation tested in 2013 was 3.6 percent.
- Average organic matter of 12 fields in permanent hay (no rotation) since 1991 tested in 2013 was 4.1 percent.
It is logical to assume that the 4.1 percent organic matter may serve as a goal for those other fields that were under a conventional tillage system through 1991 and under no-till through 2013. The soil organic matter averages suggest a trend of soil organic matter build-up amounting to 0.3 percent increase over 15 years (0.02 percent per year) between 1998 and 2013 – slow but steady. Using this data, the goal of 4.1 percent organic matter might be reached in another 25 years or so. This would be about 47 years after the implementation of no-till planting practices in 1991. Certainly not a scientific analysis, but puts the process into perspective for this type of cropping system.
Part 2 of this series focuses on cover crop opportunities to build soil organic matter on Upper Peninsula farms.