While cover crops incorporated into a continuous no-till field crop rotation can produce enough nitrogen to complement or replace corn nitrogen fertilizer applications, which means less money spent on fertilizer applications, cover crops can also improve the health of the soil by sustaining soil microbes, earthworms and other organisms, says Rafiq Islam, who holds joint appointments with Ohio State University Extension and the Ohio Agricultural Research and Development Center.
To make continuous no-till a success, cover crops are a must, he says.
"Cover crops improve the soil structure, support microbial efficiency and diversity, facilitate drainage, reduce soil erosion and nutrient leaching, store carbon, and suppress weeds and pathogens," Islam says. "They also break up soil compaction."
Islam will discuss the use of cover crops during a workshop March 6 at the Conservation Tillage and Technology Conference. A "Soil Quality" workshop funded by North-Central Sustainable Agricultural Research and Education, which begins at 9 a.m., will offer strategies and tips for growers on everything they'll need to know about cover crops worked into a corn/soybean/wheat rotation under continuous no-till, and the positive benefits to soil, water and air quality, he said.
Cover crops Islam recommends includes oilseed radish, cereal rye, cowpea or Austrian winter pea. He calls oilseed radish a "wonder crop" for its numerous soil and water benefits.
"Oilseed radish can penetrate the soil more than 30 inches deep, which uplifts the soil and allows water drainage to be improved," Islam says. "Plus we found that it can penetrate with more than 280 pounds per square inch pressure to break up soil compaction and can be used as a natural biofumigant in organic agricultural production systems.
"Oilseed radish grows in any soil, and it suppresses nematodes and disease-causing organisms but to our knowledge, not earthworms."
Legumes such as cowpea and Austrian winter pea used as cover crops can provide 140 to 150 pounds of nitrogen fertilizer per year, enough so that growers wouldn't have to use nitrogen for any succeeding corn plantings. Also, cowpea tolerates drought.
Another benefit is the increase in earthworm populations, which can be doubled through the use of cover crops, Islam said. Earthworms, which are a good indicator of soil health, enhance soil health through recycling nutrients and encouraging soil aeration, porosity and percolation.
The Conservation Tillage and Technology Conference is sponsored by OSU Extension, OARDC, Northwest Ohio Soil and Water Conservation Districts, the U.S. Department of Agriculture's Natural Resources Conservation Service, the Ohio No-Till Council, and North-Central Sustainable Agricultural Research and Education.
The full schedule and registration information can be found at http://ctc.osu.edu. Participants may register online or by mail. Registration for the full conference is $80 (or $60 for one day) if received by Feb. 24. Information is also available in county offices of OSU Extension.