A combine harvester includes a housing, a separating system mounted within the housing for separating a seed material from a straw material, a cleaning system including a cleaning fan configured to produce a motive flow of air, a straw chopper operable to chop the straw material from the separating system into a chopped straw material, a spreading system positioned downstream of the straw chopper and configured to disperse the chopped straw material outside of the housing of the combine harvester, and an air discharge channel located downstream of the straw chopper and above the spreading system and configured to discharge a portion of the motive flow of air produced by the cleaning fan.