Agricultural pneumatic distribution machine for distributing at least one granular material to be distributed, preferably seed and/or fertilizer, having - at least one distribution head, which is connected to a metering member via a delivery line, wherein the distribution head has a plurality of outlet openings (36a, 361) and each outlet opening (36a, 361) is connected pneumatically to at least one dispensing element via a dispensing line (44, 44a-441), wherein at least some of the dispensing lines (44, 44a-441) are able to be blocked by means of a switching element such that the entry of an air/material mixture into the corresponding dispensing line (44, 44a-44l) is prevented, wherein at least some outlet openings (36a, 361) are respectively connected pneumatically to the delivery line via a return line (38, 38a-381) and the return lines (38, 38a-381) each have a branch, which is connected to a bypass line that leads into the associated dispensing line (44, 44a-44l) and wherein a feed region comprises at least the end region of the delivery line, the distribution head and the return lines (38, 38a-381) and the returned material can circulate within the feed region; and - a control system, which is configured to control the metering member, characterized in that the control system is configured to control the metering member on the basis of the advancing rate of the distribution machine, a delivery time of the material to be distributed from the metering member to the distribution head, and a delivery time of the material to be distributed from the distribution head to the dispensing elements, such that at any time, the currently required total quantity of material to be dispensed is already present at the distribution head, wherein, at any time, the determined required total quantity of material to be dispensed is already circulating in the return region and, before at least one previously blocked dispensing line (44, 44a-441) is opened up, a required sub-quantity is fed without delay to the corresponding dispensing line (44, 44a-441). - at least one distribution head, which is connected to a metering member via a delivery line, wherein the distribution head has a plurality of outlet openings (36a, 361) and each outlet opening (36a, 361) is connected pneumatically to at least one dispensing element via a dispensing line (44, 44a-441), wherein at least some of the dispensing lines (44, 44a-441) are able to be blocked by means of a switching element such that the entry of an air/material mixture into the corresponding dispensing line (44, 44a-44l) is prevented, wherein at least some outlet openings (36a, 361) are respectively connected pneumatically to the delivery line via a return line (38, 38a-381) and the return lines (38, 38a-381) each have a branch, which is connected to a bypass line that leads into the associated dispensing line (44, 44a-44l) and wherein a feed region comprises at least the end region of the delivery line, the distribution head and the return lines (38, 38a-381) and the returned material can circulate within the feed region; and - a control system, which is configured to control the metering member, characterized in that the control system is configured to control the metering member on the basis of the advancing rate of the distribution machine, a delivery time of the material to be distributed from the metering member to the distribution head, and a delivery time of the material to be distributed from the distribution head to the dispensing elements, such that at any time, the currently required total quantity of material to be dispensed is already present at the distribution head, wherein, at any time, the determined required total quantity of material to be dispensed is already circulating in the return region and, before at least one previously blocked dispensing line (44, 44a-441) is opened up, a required sub-quantity is fed without delay to the corresponding dispensing line (44, 44a-441).