The present invention relates to a mechanical weed seed management system and device for use on a harvester. The device comprises a plate for providing a barrier between straw and chaff waste after discharge from a harvester a chute for catching, directing and depositing the straw waste to the ground and a trough comprising a means for transporting material through its length, for catching, transporting and depositing the chaff waste on top of the straw waste on the ground, wherein the trough is of a depth greater than 150mm. The system for the management of weeds in farmable land comprises the use of the device.
