In the Corn Belt, Cover Crops Keep Soil in Place
Even in the middle of the Corn Belt, cover crops can co-exist in a no-till, corn/soybean rotation.
Ross Pauli, who farms rolling soils near Edwards in Peoria County, added cover crops to his corn/soybean system four years ago, after he noticed dramatic yields in corn planted into broken-out hay ground.
"We would have hay growing on a field for five years. We would kill the hay and go into corn. It was poor ground, but it produced 200 bushel per acre corn!" he explains. "Four years ago, we got rid of the cows and began growing cover crops."
Pauli was a featured speaker on the Illinois Confluence Tour on July 8. He uses a variety of tactics to keep soil in place, and to prevent nutrient runoff. Cover crops and no-till work in concert to make that happen, says Pauli, who began no-tilling in 1983. He converted from a tillage system that centered around the moldboard plow.
"Before moving into a conservation tillage system, we would see dirty snow. When we began using a chisel, we'd see less dirt in our snow. Now, we don’t see any," says Pauli, who serves on the board of directors of the Peoria County Corn and Soy Promoters Association.
Soil conservation is the reason Pauli switched to no-till. He found over time that continuous no-till eliminated gullies and runs on his farms. With erosion under control, cover crops add diversity to the soil, promote soil health and keep the soil alive, explains Josh Joseph, resource conservationist with Peoria County Soil and Water Conservation District.
"A number of cover crops will put nitrogen into the soil, or pull it from deep and fix it into the soil profile, where corn can more easily use it," Joseph says. "Planting a cover is cheaper than applying anhydrous ammonia, plus with anhydrous there is less nitrogen available in the summer when it is needed."
In ground going to corn, Pauli plants cereal rye, crimson clover (for nitrogen fixation) and tillage radishes (to create deep channels for water and roots to follow). Last year, he had the cover crop flown on, and they died overwinter. This year, he will try oats and tillage radishes.
In ground going to soybeans, cereal rye will be planted the fall prior, either flown into standing corn, or planted with a no-till drill immediately following corn harvest. "Cereal rye works well in front of soybeans," he says. "It doesn't work well in front of corn."
"We don't want to lose nutrients, and rye can help protect them from leaching," he says.
If planting only cereal rye into corn, Pauli might apply 60 pounds of seed per acre. If he blends annual rye, tillage radish and crimson clover, he will plant 10 to 12 pounds of each crop with the grain drill or if via plane, 15 to 20 pounds of each. Seed applied via airplane generally doesn’t get good seed-to-soil contact, thus the need for more pounds per acre.
Cover crops aren't cheap. Pauli estimates the cost to buy and plant the seed is $30 per acre. But, the covers help keep soil in place, even in large rain events of two or more inches. Plus, they accelerate organic matter improvement. Since he began farming in 1980, organic matter has improved from about 1.5% to over 3%.
He may add wheat to his crop rotation, because the wheat stubble works ideally in a cover crop system. Plus, it adds even more diversity to his soils.
Editor's Note: Agriculture.com/Successful Farming magazine contributing editor Bill Spiegel produced this report.