The Relationship Between Machinery Traffic and Corn Yield Reductions in Successive Years

ABSTRACT TO understand and assess damage to corn production by soil compaction generated by vehicular traffic, a randomized complete-block design was selected to lay out plots to comprise treatments of 1, 5, 10 and 15 passes with contact pressures of 62, 41 and 31 kPa and a control of zero traffic. These experiments were performed in two successive years in a Ste. Rosalie clay soil to incorporate the effect of weather conditions. Agronomical treatments were kept the same for all the plots. During the 1976 growing season, a yield loss of 40 to 50 percent was obtained in plots with higher contact pressures and multiple passes. The experiment in 1977 showed losses up to 30 percent, the highest yields occurring in the moderately compacted plots. Models of plant output parameters in terms of vehicular traffic were com-pared.