Nitrogen and Carbon – Two More Benefits of Annual Ryegrass

In the last blog post, we addressed the myth of annual ryegrass being hard to manage. Follow good control procedures and it is not an issue whatsoever.

Two other assets of annual ryegrass: it creates a savings in expenditures for nitrogen during the season, and it adds considerably to the organic matter in your soil, thus boosts your carbon uptake in the soil as well.

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First thing: nitrogen is a key to production. In years past, when cultivation was more popular, nitrogen was increasingly important and expensive. Now, with annual ryegrass as a cover crop, you can actually plan on reducing your nitrogen input. Why? Because annual ryegrass sequesters available nitrogen in the soil during it’s growth. Then, when it’s terminated in the spring, the residue gives up the stored nitrogen, often just in time for the new crop of corn. In many cases, having annual ryegrass decaying in the field means reducing or eliminating the nitrogen boost in June.

Secondly, as the annual ryegrass roots decay (after the cover crop is terminated in early spring), the result is more organic matter, which means more carbon sequestered in the soil, plus more food for a health soil biology.

Finally, when the roots decay, it leaves the earth more pliable, easier for rain to infiltrate, and easier for corn roots to follow. Because annual ryegrass roots grow to depths of five feet and more, it allows corn roots to access that same depth, beyond compaction and into more nutrients like P and K.

It’s amazing that cover cropping, despite it’s proven benefits, is still practiced so infrequently. While it’s great to learn that in some states, 10 percent or more of farmers are using cover crops, it’s discouraging that upwards of 90 percent are still relying on older ways: deep ripping of depleted soils and adding more fertilizer than would be needed if cover crops were utilized.