A method and system for use with the combine to modify tailings conveyed to a cleaning system grain bed. Methods and systems are provided that utilize one or more sensors to detect uneven distribution of crop material in the grain bed, which provides information for a controller to determine whether adjustments to a tailings distribution system is needed to encourage even distribution of crop material in the grain bed. Elements in the tailings distribution system can be adjusted to alter direction of tailings conveyed to the grain bed to encourage even distribution of crop material on the grain bed. The system may also inform an operator of suggested manual adjustments to mitigate the non-uniformity.