A system and method for controlling spreader output from a harvester (10) includes a distribution chamber (22) for receiving an agricultural material removed from a field. The harvester (10) includes a spreader system (24) configured to distribute the agricultural material onto the field, and an opening (30) configured to receive the agricultural material from the distribution chamber (22). Moreover, the distribution chamber (22) includes a first panel (36) rotatably coupled to a first side (32) of the distribution chamber (22), and a second panel (46) rotatably coupled to a second side (34) of the distribution chamber (22). The first and second panels (46) are configured to direct the agricultural material toward the opening (30) of the spreader system (24). An angle (40) of the first panel (36) is independently adjustable to control a first amount of agricultural material directed toward a first inlet portion (42). An angle (50) of the second panel (46) is independently adjustable to control a second amount of agricultural material directed toward a second inlet portion (52).
