Effect of Previous Crop Rotation and Tillage on Moldboard Plow Draft in a Loam Soil

A field experiment was established by the University of Guelph on loam soil at Elora, ON to examine the effect of soil and crop management on soil parameters. Management treatments included crop rotations of corn and forages with different lengths of time for each crop. Conventional till (CT) or minimum till (MT) was applied to plots in the corn phase, and no-till (NT) was applied to the forage crops. At the end of the experiment, the plots were split, and one half was subjected to CT and the other half was subjected to NT. Corn was planted in both halves (CT and NT) of each plot. In the following spring, the entire site was moldboard plowed, cultivated and planted to corn. Energy for moldboard plowing was measured with the Agriculture and Agri- Food Canada instrumented research tractor. Results showed that the previous crop management (rotation) treatment did not have a significant effect on either moldboard plow draft or tractor fuel consumption although there were some significant differences among pair-wise comparisons of management treatments. Tillage treatment in the previous year (CT and NT), and interaction of tillage and previous crop management treatment had a small but significant effect on plow draft. The sub-plots that were in NT the previous year had 1.7% and 1.5% lower plow draft and tractor fuel consumption respectively than those that were in CT. The results support the widely held opinion that NT improves soil structure, and suggest that the soil loosening effect of CT is short lived. .