Just saying you're growing a cover crop is no longer enough. You need to specify which type of cover crop you're growing, and hopefully you had a reason for picking the different species and varieties of those species that you selected.

The reason for specifying is that in a replicated Beck's Practical Farm Research Study at Atlanta, the same hybrid was no-tilled into six different cover crop mixes. Price range of the cover crop seed ranged from $12 to $35 per acre, not counting application cost. Yield of corn varied from 206.5 to 164.4 bushels per acre in this no-till field. That means net income varied from $1,206.35 to $940.29 per acre.

Annual ryegrass seems effective: Based on one year's data it appears that in the Beck study, at least, annual ryegrass was very effective.

It's a one-year study from a very unusual year, although these plots received more rain than in many other parts of the state. Toby Ripberger, coordinator of all Practical Farm Research Plots for Beck's Hybrids, says they intend to repeat this experiment again this growing season.

The cheapest blend produced the highest yield and highest net return. N Vest Soilbuilder is a combination of two deep-rooted annual ryegrass varieties that reportedly have good winter hardiness.

One thing Ripberger will be watching for is how the cover crops survive this winter. Last winter was so mild that the crops grew larger than normal. It's good in that it captured more N and produced more material to return to the soil to help build up organic matter. However, in general, the cover crops were harder to kill and took longer to decompose than in previous years. The top yield from the mix of two annual ryegrass species was 25 bushels per acre better than the plot acreage.

Beck's Soybean Bean Builder mix of annual ryegrass, Groundhog radishes and Appin turnips performed second best last year. Beck's Corn Champion Mix of crimson clover, plus the same varieties of turnips and radishes produced the lowest yield and lowest net income.