Abstract: A self-propelled cutting machine has one cutting unit positioned in front of each forward wheel and one cutting unit positioned behind the common transverse axis of the forward wheels so that the three cutting units cut a single swathe. Each cutting unit has a cutting element with a driven shaft and a plurality of flail elements spaced along the length of the driven shaft and each rotatable with respect to the drive shaft axis about a flail element axis that is parallel to and spaced from said axis. The flail cutting element in each cutting unit can be replaced by a helical cutting reel.