Abstract: In a field chopper or chopper forage harvester, a disc wheel chopper is mounted within a housing for rotation about an axis with an elongated discharge tube opening from the radially outer surface of the housing. A crushing device is located within the discharge tube and is positioned to receive the material carried along the circumferentially inner surface of the housing by the disc wheel. The discharge tube forms an air transport duct located radially inwardly of the crushing device relative to the axis of the disc wheel chopper so that air flow generated by the disc wheel bypasses the crushing device and flows through the air transport duct for supporting the flow of material exiting from the crushing device.