Forage research at The Ohio State University has shown that winter cover crops of annual ryegrass and a mixture of oat plus winter rye provided forage dry matter yield and nutritive value sufficient to extend the grazing season. Satisfactory animal gains were also reported from the two-year study conducted at Columbus.

Annual ryegrass, and a mixture of oat plus winter rye were planted no-till following corn silage harvest in September 2006 and 2007.

The oat plus winter rye yielded more total forage than annual ryegrass mainly because the ryegrass was slower to start growth in the spring and was killed in anticipation of an early corn planting date before it reached a rapid growth phase.

Compared to the no cover crop treatment, annual ryegrass and the oat plus winter rye mixture had three- to fivefold greater root yield, threefold greater soil microbial biomass in the spring, and 23 percent more particulate organic carbon concentration in the 0- to 6-inch soil depth.

The researchers indicated that the cost of producing the cover crop forage, which included glyphosate applied before planting, seed, planting operation, and nitrogen fertilizer was $68 per acre for annual ryegrass and $84 per acre for the oat plus winter rye mixture. The cost per animal unit grazing day was $1.12 for annual ryegrass and $1.19 for oat plus winter rye, which did not include fencing, watering, and labor.

The researchers concluded that using winter cover crops for forage within a no-till corn silage system has the potential to provide supplemental forage for harvest or for livestock grazing without detrimental effects on subsequent corn silage production, and with the added benefit of increasing soil carbon. The study was reported in the Agronomy Journal, Volume 101, Issue 5, 2009.