Some tried cover crops this spring and crashed and burned. Some will dust themselves off and try again. Others will ditch it. That is the nature of all things agricultural – they're tied to the weather which can't be predicted in advance.
"You need people who have done it as a network you can call when you run into a situation you aren't familiar with," says Barry Fisher, a Natural Resources Conservation Service agronomist who works with cover crops. "You need to be flexible and make changes."
Fisher recently inspected a pit where soybeans were no-tilled into 6-foot tall rye earlier this year. The stand is very good, and the crop is in good shape for this time of year.
"Soybeans work well behind cereal rye for several reasons," Fisher says. "The rye ties up nitrogen, especially last year after corn left so much behind. Soybeans don't care if there is nitrogen available or not. In fact there is some reason to believe that if there isn't, but bacteria that fix nitrogen are in the soil, nodulation will happen sooner.
Fisher found nodules down to 20 inches below the surface in the pit he inspected recently. "Cereal rye is also very good at preventing weed growth," he says. "In fact, some farmers who are having trouble with marestail plant cereal rye ahead of soybeans on purpose. The results indicate that it definitely gives them a jump on controlling marestail and other weeds."
Conversely, a cereal rye cover crop ahead of corn can be a problem if not managed correctly," Fisher says. "You need a lot of N early in the season for corn. That's when it makes key decisions about ear size. If you don't apply enough additional N, the rye will tie up the nitrogen and it won't be available to the corn until later in the season when the dead cover decays. That's too late for corn, which needs nitrogen there early."