Submitted to: Georgia Water Resources Conference
Publication Type: Proceedings
Publication Acceptance Date: 4/1/2009
Publication Date: 4/27/2009
Citation: Endale, D.M., Hook, J., Sullivan, D.G., Lee, D., Reeves, D.W., Faircloth, W.H., Rowland, D. 2009. Potential of high residue conservation tillage to enhance water conservation and water use efficiency in corn production in the Southeast. 2009 Georgia Water Resources Conference, April 27-29, 2009, University of Georgia, Athens, GA. CDROM.
Interpretive Summary: Recent recurrent drought in the Southeast has brought the issue of water availability, use, and use efficiency to the forefront of public debate. Georgia will soon begin drafting regionally-based water development and conservation plans following the adoption of its first Comprehensive State-wide Water Management Plan in February 2008. Conservation-tillage based agriculture production should be included among the management tools available to achieve the objectives of the plan, especially in irrigated agriculture. We highlight the potential of this problem using corn production in Georgia as an example. In 2007 Georgia growers harvested 450,000 acres of corn, 290,000 acres of which were irrigated. Corn requires approximately 25 inches of water from rainfall and/or irrigation for high yield. Using the 2000 to 2008 rainfall data from Camilla, GA in Mitchell county the highest corn producing county in Georgia as an example, it would have taken a net average annual irrigation of approximately 78 billion gallons for maximized corn yield from the irrigated corn lands. Assuming an extra 20% infiltration from rain and irrigation under conservation tillage, total annual savings would amount to approximately 20 billion gallons of irrigation water. This is equivalent to the annual water need of 350,000 people. Scientists at USDA-ARS in Watkinsville and Tifton, GA, have shown infiltration under conservation tillage in Coastal Plain soils can be up to 50% greater than under conventional tillage. In a multi-year study in Tifton and Camilla, GA, USDA-ARS (Watkinsville) and University of Georgia (Tifton) scientists found that yields of conservation tillage corn were equal or up to 20% better than conventional tillage corn. Growers, extension agents, local, state and federal agencies should seriously consider conservation tillage among the management tools available to achieve production and conservation goals. In Georgia alone, irrigated corn, cotton, and peanut production covers 1,150,000 acres.
Technical Abstract: Following the adoption of its first Comprehensive State-wide Water Management Plan in early February 2008, Georgia is on course to drafting regionally-based water development and conservation plans. Conservation tillage-based crop production can be one of the management tools available for achieving the goals of the plan and should be considered. In addition, enhanced research support is required to develop conservation tillage management practices tailored to specific crop production systems by region. In this paper we highlight potentials of high residue conservation tillage to enhance water conservation and water use efficiency using corn production as an example.