Agricultural machine for the harvesting of plants, in particular of fodder, this machine being movable in a direction of advance and comprising: - a chassis, - at least one support arm articulated on the chassis and movable with respect to the chassis between a work configuration in which the support arm extends laterally with respect to the chassis, and a transport configuration in which the support arm is folded such that its overall dimension perpendicularly to the direction of advance is reduced, - at least one work tool comprising an inner lateral end and an outer lateral end, and being able to occupy at least one work position in which the work tool acts on plants lying on the ground, and at least another position, - a connecting device, by means of which a frame of the work tool is connected to the support arm, this connecting device allowing, at least when the support arm is in the work configuration, a first movement of the work tool with respect to the support arm during which the inner lateral end and the outer lateral end of the work tool move vertically with respect to the support arm and in the same vertical direction with respect thereto, this connecting device allowing a second movement of the work tool to be operated with respect to the support arm, this second movement being transverse to the direction of advance and substantially horizontal considering the support arm in the work configuration, and the means making it possible to operate this second movement independently of the first movement of the work tool with respect to the support arm, characterized in that the connecting device comprises at least one arm oriented essentially in the direction of advance when the support arm is in the work configuration, that this arm is articulated on the support arm about a first axis which is oriented transversely to the direction of advance and substantially horizontally when the support arm is in the work configuration, and that this arm can, by pivoting about this first axis, move vertically with respect to the support arm in the work configuration, such that the work tool can move vertically with respect to the said support arm. - a chassis, - at least one support arm articulated on the chassis and movable with respect to the chassis between a work configuration in which the support arm extends laterally with respect to the chassis, and a transport configuration in which the support arm is folded such that its overall dimension perpendicularly to the direction of advance is reduced, - at least one work tool comprising an inner lateral end and an outer lateral end, and being able to occupy at least one work position in which the work tool acts on plants lying on the ground, and at least another position, - a connecting device, by means of which a frame of the work tool is connected to the support arm, this connecting device allowing, at least when the support arm is in the work configuration, a first movement of the work tool with respect to the support arm during which the inner lateral end and the outer lateral end of the work tool move vertically with respect to the support arm and in the same vertical direction with respect thereto, this connecting device allowing a second movement of the work tool to be operated with respect to the support arm, this second movement being transverse to the direction of advance and substantially horizontal considering the support arm in the work configuration, and the means making it possible to operate this second movement independently of the first movement of the work tool with respect to the support arm,