Tractor disc harrows are attachments that are used to eliminate the field divets and dirt piles after plowing. Consisting of four separate groups of discs: two discs in the front and two discs in the rear, disc harrows are among the best and most efficient tools used to pulverize and level soil. Disc harrows work by cutting through soil as they rotate. Due to their slightly curved camber, the axle is offset, and they slice and push away the soil as you pull them with your tractor. Find a great deal on disc harrows for sale in the US: