Soil and Water Conservation Districts are getting more and more involved in the promotion of cover crops. The reason is simple: over the past 20 years, it has been shown that cover crops protect the soil in ways that no-till alone cannot.
(Photo: Rod Rose, Lebanon Reporter. A Boone County farmer discusses core samples comparing fields where cover crops are planted, compared to samples from fields without. He discussed the benefits of cover crops.)
Here are some of the reasons he mentions:
- Leaving green in the field year-round prevents soil run-off and loss of precious nutrients.
- The residue from past crops, including cover crops, becomes important food for the biological diversity of the soil. Likewise, residue begins to build the depleted organic matter and carbon carrying capacity of the soil
- Deep roots – especially from annual ryegrass – break up compaction. This is so important in soils that prevent corn and soybean roots from going below the fragipan layer. Once broken, the corn roots can grow to depths of 5 feet and access moisture and nutrients…especially important in dry growing years
- Annual ryegrass is a nitrogen sink, soaking up excess N when growing and giving it back to the soil when the residue decays in early summer, just when the corn needs it most
- All these reasons add up to more profits – fewer field inputs, better soil health and bonus yields.
Here’s a link to that article, which mentiones annual ryegrass rooting capabilities, and the popularity of cover cropping systems in the Midwest.