Cotton growers in the Southeastern United States can deal with periodic droughts by using conservation-tillage and fertilizing with poultry litter, Agricultural Research Service (ARS) scientists report.
Agricultural Engineer Dinku Endale and agroecosystems ecologist Harry Schomberg at the ARS J. Phil Campbell, Sr., Natural Resource Conservation Center in Watkinsville, Ga., conducted a study that found no-till cotton fertilized with poultry litter yielded 42 percent more than conventionally-tilled cotton fertilized with ammonium nitrate.
Using no-till practices alone increased yield by 33 percent over conventional-tillage practices, they found.
According to Endale, many soils in the Southeastern states have low water-holding capacity and form nearly impervious layers that restrict root growth. If roots can't penetrate deeply enough to access soil water reserves, the drought effect is worsened.
No-till cotton was able to capitalize on carry-over water in the soil, faring better after being established. That helped it to survive into the blooming phase. Conservation-tillage protects the soil surface and allows more rainwater to penetrate.
Long-term use of practices such as no-till allows crop residue to accumulate on soil surfaces, which helps build soil structure, increases rainwater filtration, reduces evaporation, and increases the biological activity that helps improve nutrient cycling.
The bottom line is that producers can increase their ability to produce cotton during drought periods by implementing practices that help conserve soil and protect the environment.
ARS is the U.S. Department of Agriculture's chief scientific research agency.