|Baker, J - IOWA STATE UNIVERSITY|
|Ressler, D - IOWA STATE UNIVERSITY|
|Horton, R - IOWA STATE UNIVERSITY|
Submitted to: Integrated Crop Management Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: November 18, 1998
Publication Date: N/A
Technical Abstract: Localized compaction and doming (LCD) using a custom-made applicator is proposed as a way to alter water flow paths around a knife injected nitrogen (N) fertilizer band and reduce N leaching. On croplands where N is limiting, N preserved in the root zone is available for crop uptake and can lead to increased yield. Results of recent studies in lysimeters, field plots, and tile drained research plots have indicated that localized compaction and doming over a line source of N fertilizer reduces nitrate leaching and improves N-use in efficiency Midwestern rainfed corn, particularly in years that have greater than average rainfall after N application. Diversion of infiltrating/percolating water away from the zone of N application might also be accomplished by using the point injector fertilizer applicator to inject N fertilizer into the ridge in ridge tillage. In this system, the ridge diverts rainwater into the interrows. Additional research is needed to refine the concept of diverting water flow paths around applied N and the methodology/ equipment needed to execute the concept in production systems. Two management applications of this concept that deserve future study are the use of compaction and doming to protect fall-applied N against leaching and the use of an applicator designed for this purpose while cultivating for weed control.