A stalk-chopper, in particular for a machine for harvesting maize, comprising: - a hollow casing (124) having a central portion (126) and two box-section arms (128) that extend in cantilever fashion from the central portion (126) according to a U-shaped configuration, the box-section arms (128) being set at a distance from one another in a transverse direction and having respective distal ends (128a) set at a distance from the central portion (126) in a longitudinal direction (A)； - two rotating output members (130) projecting on the outside of said box-section arms (128) at the respective distal ends (128a) of said box-section arms (128), the output members (128) being carried in a rotatable way by the respective arms (128) about respective mutually parallel axes of rotation (E)； - two rotary cutting devices (132) connected to respective output members (130) and having respective cutting diameters (D) partially overlapping one another； and - a transmission device (138) housed within said hollow casing (124) and provided for driving said output members (130) in rotation in concordant directions.
