Spring will come again, and with it, another planting season. Do your planting plans for 2020 include spring tillage? Are your spring tillage plans set in stone, or will they be subject to change depending on weather conditions? Do you plan to no-till, but maybe run over fields before planting with a vertical-tillage tool to help dry them out if it’s a wet spring?
However innocent a light tillage pass may seem, you may have to live with the long-term consequences and impact to your soil. With many Indiana soils, the greatest potential for causing soil compaction occurs a couple of days before the soil is truly dry enough to plant.
If you run a tillage tool over the soil to “dry it out,” you may be doing so at a time when you risk causing a layer of soil compaction that will remain possibly into the next growing season. Depending on the tool and operating speed and depth, you risk causing as much compaction as a disk would cause.
If you have ever seen a new road being constructed, you’ve observed contractors using a disk to prepare and compact the soil. The compaction layer caused by a vertical-tillage pass at the wrong time could be enough to prevent proper rooting of your corn or soybeans, reducing potential yields in a dry summer.
How do you feel about soil crusting? Is it one of your primary concerns after a spring rain, especially if you just planted soybeans? Crusting is directly related to tillage, and generally doesn’t occur in untilled soils that have developed good soil aggregation.
When a rain event occurs, soil particles are dislodged on the soil surface and fill pore spaces on the surface. Soil health experts call this the first stage of erosion. If the weather turns hot and dry, crusting will occur due to the breakdown of soil structure on the surface.
Research has shown that in long-term, never-tillage soil health systems, one tillage pass can destroy what it took 10 years to build. Yes, that can even include a light tillage pass with a vertical-tillage implement.
Growers using soil health management systems that include no-till and cover crops are finding they can reduce soil compaction and crusting. Since the soil isn’t tilled, the soil structure and aggregation remain intact, and crusting doesn’t occur after large rain events.
That same structure and aggregation provides better infiltration. As the system matures, you will find your soil is more resilient, less likely to compact, and more forgiving during times of excessive moisture. In some cases, soil structure is so much improved that it allows harvest and planting to occur when neighboring farmers using conventional systems aren’t able to be in the fields.
Remember, successful no-till and cover crop systems require a heavy dose of patience. Do your research, talk to successful no-till and cover crop farmers, attend local and national field days and conferences, and resist the temptation to use unnecessary spring tillage.
Donovan is a district soil conservationist with the Natural Resources Conservation Service. He writes on behalf of the Indiana Conservation Partnership.