With corn harvest underway in parts of the Midwest, some fields are already being tilled in preparation for spring planting. But what type of tillage might be best following this year’s drought?
“It’s a good question,” says Emerson Nafziger, crop scientist with the University of Illinois Extension. He says tillage following extended periods of dry weather often brings up large, hard clods. But initial reports this year show the soil is breaking apart better than expected.
“Expect soils to be mellower than normal during fall tillage and match the tillage operation, if any is needed, to this condition,” Nafziger advises. “That includes paying attention to how much residue is being left on the surface.”
He says tillage last fall and field operations this year took place when soils were relatively dry, which resulted in less than normal compaction due to heavy equipment on moist soils. Other factors associated with a drought-damaged corn crop, he adds, may actually improve field conditions for the next corn crop.
“For example, corn that has slow growth due to stress in mid-season does not produce much lignin, so its residue is softer, it breaks down faster, and planting into it is easier,” he says. “There also is less residue to contend with.”
As a result, Nafziger expects that we could see more use of reduced tillage methods such as vertical tillage and strip tillage, which disrupt less soil than deeper tillage methods and leave a little more residue on the surface.
“Other than maybe adjusting a tillage implement to leave more of the limited amount of residue on the surface, and maybe a little more use of 'vertical' tillage instead of deeper tillage, I’m not sure we’ll see a lot of adjustment, at least adjustment that costs money, such as a new implement. “
Nafziger says there is a tendency for farmers with a poor crop to want to get the crop residue tilled in the ground after harvest tilled. “Maybe this is a way to get rid of memories of the crop drying up in July and to start looking forward to what most expect to be a better season next year.”
However, he doesn’t expect this tendency will cause farmers to directly change their tillage practices. “That is, people generally don’t do full-width just to make fields look better,” he says. “But there may be less need for deep tillage to break up compaction, and something like strip-tillage might work better than it normally does in cornstalks.”