Many farmers believe that if they switch from conventional to conservation (no-till) farming, it'll take several years before they start seeing benefits. But Agricultural Research Service scientists in Auburn, Ala., and cooperators have found that when the move to no-till farming is done correctly, yields increase right away.
The ARS and Alabama Agricultural Experiment Station scientists started their research in 2000 on a 20-acre field, with conventional-tillage on half of the field and conservation-tillage on the other half. In a rotation of cotton and corn crops, cotton grown with conservation-tillage produced 12 to 24 percent higher yields each year of the study's first three years, compared to the conventionally-tilled cotton.
The research project was led by ARS Agronomist D. Wayne Reeves, now research leader of the agency's J. Phil Campbell, Sr. Natural Resource Conservation Center in Watkinsville, Ga.; Agricultural Engineer Randy L. Raper of the ARS National Soil Dynamics Laboratory in Auburn; and Auburn University Soil Scientist Joey N. Shaw.
The team discovered that as long as there's an adequate amount of residue from a cover crop, transitioning to conservation-tillage provides immediate benefits.
Farmers should not terminate the cover crop too early. Instead, they should plant the cover crops within recommended planting windows and let them grow until they're three to five feet tall and spring planting is three to four weeks away. This will insure that there is sufficient residue on the soil surface to reduce soil erosion and trap rain to maintain adequate soil moisture through the planting season.
The group has found that non-inversion plows--which will not disturb the crop residue--can be used to address soil compaction problems. But the farmer should stick to conservation-tillage with high production of cover crop residue as much as possible to reap the financial — and environmental — rewards.
ARS is the U.S. Department of Agriculture's chief scientific research agency.