Schwab, G.O., Taylor, G.S., Fouss, J.L.

The effects of various drainage systems and different levels of N treatments on corn (Zea mays) yields were evaluated for a fine‐textured lakebed soil during a period of 3 years. The drainage treatments consisted of undrained plots, surface drained, the drained, and a surface and tile drained combination. Excess wetness was provided each year by sprinkling all plots in June and July. The three drained treatments gave significantly higher yields than the undrained treatment, and N increased corn yields significantly at all drainage levels.

An economic evaluation of the drainage systems with a N application of 100 lb/acre showed that the benefit/cost ratio for surface drains was 10:1; tile drains 6:1; and the combination tile‐surface drainage system 4:1, when compared to the un drained treatment. The study indicated that the surface drainage system gave the greatest benefit per dollar invested in the drainage system.