A two-year on-farm study was conducted in a poorly drained, heavy clay soil in the Red River Valley, Manitoba,
Canada, to explore six tillage alternatives. The six tillage methods consisted of a field cultivator (conventional tillage), a tandem
disk, chisel plows with reversible shovels, twist shovels and narrow sweeps, and no-tillage. No-tillage gave the overall
best results for the studied condition as it produced better or comparable yield, speed of emergence, and plant population,
while requiring no tillage operations and leaving the most crop residue cover to protect against erosion. Chisel plow with
reverse shovels could also be an alternative for clay soils, as it required relatively lower drafts and smaller amounts of incorporated
residue in the seedbed, while giving crop performance that was comparable to the conventional tillage. The tandem
disk resulted in the least residue cover (40% to 45%) in the field, which originally had 67% to 70% residue cover. The tandem
disk plots contained the highest amount of incorporated residue (1.13 Mg ha-1) in the seedbed. Furthermore, the tandem disk
resulted in a lower speed of crop emergence and plant population than the conventional tillage. Therefore, producers in the
region would be taking a high risk with disking tillage.