Principal investigators: H.A. Torbert
Associated with: USDA-ARS National Soil Dynamics Laboratory
Reduced tillage, poultry litter applications, crop rotations, and winter cover cropping are management practices that could be used with conservation tillage systems to increase yields compared to conventional monoculture systems. An ongoing study is evaluating cropping sequences of corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and corn–soybean rotations with wheat (Triticum aestivum L.) covers in conventional, strip, and no-tillage (no-till) systems, following poultry litter additions to wheat cover. The study has been conducted since 1991 on a Hartsells fine sandy loam (fine-loamy, siliceous, subactive, thermic Typic Hapludults) and some results have been reported. Poultry litter (112 kg N/ha) was applied to wheat each year in fall. Wheat not receiving poultry litter received equivalent inorganic N. Corn was fertilized with inorganic fertilizer in spring with 56 kg N/ha at planting followed by 168 kg N/ha three wk after emergence; soybean received no fertilizer. To date, the study suggest that poultry litter used for these crop rotations in conservation tillage systems could increase sustainable yield production.
Watts, D.B., H.A. Torbert, S.A. Prior, and G. Huluka. 2010. Long-term tillage and poultry litter impacts soil carbon and nitrogen mineralization and fertility. Soil Sci. Soc. Am. 74:1239-1247.
Watts, D.B., and H.A. Torbert. 2011. Long-Term tillage and poultry litter impacts on soybean and corn grain yield. Agron. J. 103:1479-1486.