(By Cody Totten)
Cover crops have become of growing interest throughout Ohio and the Midwest in general. But why would a farmer who is already busy enough want to go through all the time, labor and financial input to have a winter crop that either dies off or they have to kill in the spring?
This seems completely contradictory to the mindset of any producer but there must be some reason as to why cover crops are growing in popularity and use. In fact, there are reasons for cover crops that benefit not only the soil, but the farmer’s bottom line in the long run.
Cover crops come in all shapes and forms. Some are winter kill, some have to be sprayed in the spring, others are used as winter stocked forage for livestock, and some are even used as annuals for hay. In all its various forms, the goal of a cover crop remains the same: To have something covering what would be the bare ground after the harvest is taken off the field.
Among the many benefits that cover crops provide include increases and/or improvements in soil stability, plant productivity, soil macro and micro organisms, quality of soil properties, soil structure, organic matter and organic carbon. Cover crops also provide reductions in sediment production and soil loss and in soil compaction as well.
Reduced soil erosion
When cover crops are applied to the rotation, the bare soil that you saw before in the winter and springtime is now replaced with a decaying layer of oats or a living stand of rye that helps reduce soil loss on your land.
That valuable topsoil that is needed to grow cash crops is kept in place where it should be instead of being washed into your local stream. When bare soil is no longer exposed due to the cover plant, it does not allow the soil to crust over and seal from raindrop impact.
Crusting can prevent rainwater from entering the soil and during a heavy rain, can cause significant runoff and erosion problems.The cover crop allows rainwater to penetrate the soil more rapidly because the soil is not crusted. When used with a no-till system, this increase in rainwater infiltration due to the cover crop can be quite considerable.
Organic matter increases
After the cover dies, the decomposition process begins and the soil’s bacteria and micro-organisms go to work. Using the cover as food, fungi and other bacteria produce glomalin, which helps hold particles of organic matter together and it helps those particles stay in the soil.
The micro-organisms break down the roots of the cover crop allowing for a more porous and biologically active soil environment. This increase in porosity allows for a greater infiltration of water and allows the soil to retain water for a longer time during periods where rain is scarce.
The more organic matter that is in the soil, particularly the topsoil, the more water the soil can hold. The overall increase in organic matter in the topsoil can also lead to improved stands and yields for cash crops.
Plant productivity
Plant roots tend to thrive and penetrate the soil more readily in less compacted soil because of cover crop usage than that of compacted soil. The added porosity also allows for more growth area and room to expand for the roots system as a whole.With the added root growth, cash crop plants can reach nutrients that would have been unavailable to the plant before.
Conclusion
Overall, the addition of cover crops to a crop rotation seems to have many benefits that can easily outweigh the costs. The real benefit comes in the long term, however, as multiple years of cover crops tend to see better results than that of just single-year, and you can really start to see your investment pay off.
Each producer may find a different cover crop that suits their rotation but you have to be willing to try first and that is probably the most difficult step of the whole process.
(Cody Totten is a district technician intern at the Coshocton Soil and Water Conservation District. He currently attends Wilmington College majoring in agricultural production with a minor in chemistry.)
