Just because you say you're going to plant cover crops this fall doesn't tell someone what your plans really are. Are you planting annual ryegrass? Are you going with rye or wheat? Or maybe you're planting forage radishes? Are you trying to loosen up the soil or capture nitrogen, or do you want to improve soil health and set up a system that recycles nutrients out of a decaying crop and leaves them ready for the next crop?
Stephanie Smith, field agronomist in northeast Indiana for DuPont Pioneer, says that you should select which cover crops you're going to apply this fall based on what you're trying to accomplish in the field. Many growers in your area are leaning toward annual ryegrass in a mix with oilseed radish. The mix of two different plants accomplishes something that one of the two couldn't do by itself.
"What the annual ryegrass does is produce lots of roots," she notes. "You burn it down in the spring. It is good at breaking down and recycling nutrients within the soil."
If you suspect ta soil compaction problem, then you may be looking for help on breaking up deep compacted layers. That's a good time to turn to something like oilseed radishes, she says. They produce a tap root which grows well down into the soil. If conditions are right, such as enough moisture for growth of the radish but dry enough that soil layers can be broken and shattered, the radish can do a considerable amount of good at helping break up compacted layers over time, she notes.
She believes that's why annual ryegrass and oilseed radish have become a popular mix. The oilseed radish typically dies off in the winter, as do turnips, another alternative, meaning there is no problem with burn down in the spring. Many of her customers have been able to burn down annual ryegrass successfully.