While the temperatures plunge and the snow whirls, annual ryegrass top growth has been dormant for months. But under the freeze, the annual ryegrass roots continue to flourish, adding depth, girth and mass to a system that builds healthy soil in numerous ways.
The depth of rooting alone is a benefit, because it opens channels in the soil profile. Those channels, next spring and summer, will allow corn roots to seek deeper veins of nutrition and moisture. Even in a dry year, corn that goes deep will continue to thrive. And, with any normal precipitation, those root channels will help the soil absorb the rainfall rather than allowing it to run off.
Annual ryegrass has an appetite for nitrogen, too, so it becomes a storehouse of nitrogen when it grows. Then, in the spring, after it is killed with herbicide (before planting corn or beans), the nitrogen stored in the residue becomes a fertilizer for the hungry corn plants. And the massive root structure of annual ryegrass, when it is killed, that mass degrades and decomposes, increasing the carbon content and organic matter in the soil, giving worms and microbiological organisms a food source.
Because of annual ryegrass’ nature to sequester nitrogen, it’s place in the crop rotation allows you to lighten up considerably on nitrogen inputs.
For more information about annual ryegrass, why it’s beneficial and how to manage it successfully as a cover crop, you can check out this free four-page management guide. Or you can click here to view a series of YouTube videos on the subject.