Paul Jasa admits it sounds odd, but he says cover crops help break down corn residue and improve no-till efforts the next year.
“The humidity in the growing cover-crop canopy helps decompose the residue after corn harvest and the growing cover crops feed the soil microbes,” says the University of Nebraska ag engineer. “In addition, cover crops can help dry poorly drained soils to aid soil warming in the spring. The added roots help stabilize the soil and build soil structure.”
Jasa warns that a cover crop must be controlled in a timely manner so that it doesn’t dry out the soil or create too much additional residue.
Successful no-tilling requires a long-term commitment. To realize the full economic and soil-quality benefits, Randy Caviness says you have to give it more than 3 or 4 years.
“The advantages are really going to come over the long term — that’s what we found,” says the Greenfield, Iowa, farmer, who has been no-tilling for 20 years. “After 7 or 8 years, we really started noticing the difference.
“The water infiltration issues — you don’t have the runoff, the water soaks in, the root structure below the ground lets the water go in, you don’t have the compacted layer with your tillage layer that you had — that starts to disappear over time.”
A study of Indiana water sources found those near continuous cornfields had higher levels of nitrogen, fungicides…