Cover Crops, including Annual Ryegrass, Important This Year to Soak Up Residual Nitrates

The University of Wisconsin (UW) published today an invitation for Midwest farmers to use cover crops this year, especially in light of the severe drought. You can see the whole article by clicking here:

An excerpt of the article, by UW staffers Matt Ruark, Kevin Shelley and Francisco Arriaga, as well as Rock County Extension staffer Jim Stute, follows:

With a growing season like we are having in 2012, it is likely that residual nitrate concentrations in the soil will be high, especially if corn was harvested early as silage or if yields are well below expected. One benefit of planting cover crops after corn silage, small grain, or a processing vegetable crop, or after a manure application is that the cover crop can take up residual nitrate and reduce the risk of nitrate leaching between harvest and planting.

Cover crops trap nitrate. The ideal cover crops for a nitrate trap crop are grass crops that establish quickly, such as cereal rye (aka winter rye), oat, barley, annual ryegrass (aka Italian ryegrass), and sorghum-sudangrass. These cover crops also have a fibrous root system. Brassicas (e.g. radish, turnip, mustard) and legumes (clover, hairy vetch) will also take up residual nitrate, but do not establish as quickly. Radish has been popular cover crop in no-till systems and, if planted early enough, radish can take up as much or more N compared to grass cover crops during the winter, but grass cover crops can scavenge N deeper into the soil profile.

The USDA-NRCS has announced additional funding through Environmental Quality Incentive Program (EQIP) to provide financial assistance to establish cover crops. The sign up for this program runs to August 24.