Submitted to: International Workshop of Dryland Conservation/Zone Tillage
Publication Type: Proceedings
Publication Acceptance Date: December 11, 1999
Publication Date: December 11, 1999
Citation: Raper, R.L. 1999. Site-specific tillage for site-specific compaction: is there a need?. International Workshop of Dryland Conservation/Zone Tillage. Beijing, China. pp. 66-68, Dec. 11-12. Interpretive Summary: A layer of dense soil restricts root growth and increases susceptibility to drought throughout the Southeastern U. S. To increase the rooting depths of most Southeastern soils, farmers usually till to depths greater than the root-restricting layer. Using site-specific technology, a field was sampled to determine the variation in depth of this layer throughout the entire field. Significant variation was found with the depth of this layer varying from 0.25 to 0.4 m. From this predicted tillage depth, it was estimated that producers with this soil type could save 34% of their fuel costs if they could adopt some form of tillage that would adjust depth based on the soil's specific need rather than tilling to a uniform depth.
Technical Abstract: Crop root growth is often hindered in the Southeastern U. S. due to the presence of root-restricting soil layers. Tillage must be used to temporarily remove this compacted soil layer to allow root growth to depths needed to sustain plants during periods of drought. However, the use of a uniform depth of tillage may be an inefficient use of energy due to the varying depth of this root-restricting layer. Spatial cone index measurements were used to map the variability in root-restricting layers in Coastal Plains soils. From these measurements, estimations were made showing that site-specific tillage may reduce energy costs by 34% relative to the standard uniform-depth of tillage method.