The present invention relates to a weed seed management system and weed seed management device mountable on a harvester. The device includes a plate to convey straw waste after discharge from the harvester a chute to catch the straw waste conveyed by the plate, and then direct and deposit the straw waste on the ground in a first windrow and a trough having a length and a vent, the trough to convey the chaff waste along the length after discharge from the harvester, the vent aligned with the chute to deposit the chaff waste in a second windrow on top of first windrow of the straw waste on the ground, wherein the trough has a depth greater than 150 mm. The weed management system includes the harvester and the weed seed management device.
