Submitted to: Clean Water Clean Environment 21st Century Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: August 11, 1995
Publication Date: N/A
Technical Abstract: The highly productive soils of the Midwest are mostly formed in glacial deposits. These soils tend to be slowly permeable and prone to seasonal wetness. Soil drainage is required for timely planting and to protect young seedlings. During the growing season the water balance is such that evapotranspirational demand exceeds available water stored in the soil and from rainfall. The soils may be dry excessively, resulting in drought stress and soil cracking. Water table management means using the drainage system to remove excess wetness early in the growing season and then applying water back through the drainage system later by subirrigation to avoid drought stress. Water table management results in more predictable yields, allowing more efficient use of applied agrichemicals, and less opportunity for water quality problems to develop. The potential for groundwater contamination by nitrates and pesticides is reduced. Results from this research indicate that maintenance of a constant, shallow water table during the growing season by use of a subirrigation/drainage system can improve water quality, and, when combined with a high yield crop management system, can result in average soybean yields of 70 to 80 bu/ac and 190 to 200 bu/ac corn yields.