A distribution tower for an agricultural machine for spreading distribution goods, the distribution tower comprising at least: - a riser pipe for supplying an air volume flow of distribution goods into a distributor head connecting to the riser pipe; - a multitude of outflows at the distributor head for dividing the air volume flow of distribution goods into a multitude of air volume flows of distribution goods, which outflows each branch into at least one seed tube and into at least one return device; - at least one shut-off means, by means of which optionally the at least one seed tube or the at least one return device is capable of being shut off such that the air volume flow of distribution goods is optionally guided into the at least one seed tube or into the at least one return device corresponding to a position of the shut-off means; - at least one bypass channel, which pneumatically connects the at least one seed tube and the at least one return device to each other; wherein the bypass channel has at least one flow-guiding member assigned to it at at least one junction into the at least one seed tube and/or into the at least one return device, by way of which flow-guiding member an air volume flow portion is capable of being branched off from the air volume flow portion of distribution goods, characterised in that a member (49, 49') that is at least partly permeable to flow air and/or a perforated plate (50, 50') connects to the flow-guiding member such that the air volume flow portion of the air volume flow of distribution goods can flow into the bypass channel by way of a multitude of openings of the member (49, 49') that is at least partly permeable to flow air and/or by way of the multitude of openings of the perforated plate (50, 50'). - a riser pipe for supplying an air volume flow of distribution goods into a distributor head connecting to the riser pipe; - a multitude of outflows at the distributor head for dividing the air volume flow of distribution goods into a multitude of air volume flows of distribution goods, which outflows each branch into at least one seed tube and into at least one return device; - at least one shut-off means, by means of which optionally the at least one seed tube or the at least one return device is capable of being shut off such that the air volume flow of distribution goods is optionally guided into the at least one seed tube or into the at least one return device corresponding to a position of the shut-off means; - at least one bypass channel, which pneumatically connects the at least one seed tube and the at least one return device to each other; wherein the bypass channel has at least one flow-guiding member assigned to it at at least one junction into the at least one seed tube and/or into the at least one return device, by way of which flow-guiding member an air volume flow portion is capable of being branched off from the air volume flow portion of distribution goods, characterised in that a member (49, 49') that is at least partly permeable to flow air and/or a perforated plate (50, 50') connects to the flow-guiding member such that the air volume flow portion of the air volume flow of distribution goods can flow into the bypass channel by way of a multitude of openings of the member (49, 49') that is at least partly permeable to flow air and/or by way of the multitude of openings of the perforated plate (50, 50').