Submitted to: Soil and Tillage Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/22/2009
Publication Date: 6/1/2009
Citation: Simoes, P., Raper, R.L., Arriaga, F.J., Balkcom, K.S., Shaw, J. 2009. Using conservation systems to alleviate soil compaction in a Southeastern United States ultisol. Soil and Tillage Research. 104:106-114. Interpretive Summary: Most peanut producers in the Southeastern United States have not fully adopted the technologies associated with conservation systems due to peanut diseases and the massive soil disruption associated with peanut harvesting. A cotton-peanut rotation experiment was conducted to determine if in-row subsoiling combined with the use of cover crops would create a production system that would be profitable to Southern producers. Results indicated that the conservation system that consisted of large biomass cover crops and in-row subsoiling produced the greatest yields and provided the most drought resistance of any treatments. Producers who use this sustainable system should benefit from increased water storage and enhanced soil quality.
Technical Abstract: Coastal Plain soils are prone to compaction and tend to form hardpans which restrict root growth and reduce yields. The adoption of non-inversion deep tillage has been recommended to disrupt compacted soil layers and create an adequate medium for crop development. In spite of its efficacy, increased fuel prices could reduce in-row subsoiling adoption due to the cost of the operation. We evaluated three subsoiling implements against a non-subsoiled treatment with and without a rye (Secale cereale L.) cover crop on a 4-yr cotton (Gossypium hirsutum L.)- peanut (Arachis hypogaea L.) rotation experiment in Headland, AL on a Dothan loamy sand (Plinthic Kandiudult). Results showed consistently lower yields for non-subsoiled treatments (11 and 51% lower yields for peanuts and cotton, respectively). Soil strength values had a 2 fold increase or greater (1.5 to 4.0 MPa) in less than a year due to natural reconsolidation and normal vehicle traffic. On average, in-row subsoiling returned $698/ha/year for cotton and $612/ha/year more than non-subsoiled treatments. No differences between implements were found. A conservation system consisting of annual paratilling combined with a winter cover crop proved to be the most productive and profitable system.