The present invention relates to a harvesting machine with an arm comprising a first part articulated to a chassis and a second part connected to the first part and carrying a work tool, with first and second devices used for adjusting a distance between the work tool and the chassis, between minimum and maximum values, and for displacing the work tool vertically between a work position and a raised position above the ground, and with servo-control means for positioning at least one of these first and second devices in accordance with a control setpoint which determines a target height of the work tool relative to the ground. According to the invention, the servo-control means makes it possible to raise the work tool to a height substantially equal to this target height, from two transverse positions located at a distance from the chassis between the minimum and maximum values.