A chaff pan for attachment to a cleaning apparatus of an agricultural combine. The chaff pan includes a surface for receiving a flow of chaff from the cleaning apparatus. The surface has a proximal end proximate the combine and an opposing distal end. First and second side walls extend upwards from the surface about respective lateral ends of the chaff pan. The chaff pan also includes a flow control guide vane positioned on the surface of the chaff pan that extends from the proximal end to the distal end of the surface. The flow control guide vane is positioned on the surface at an angle relative to a midline of the chaff pan for directing the flow of chaff towards the midline of the chaff pan.