Abstract: A system for adjusting a tractor speed based on a performance of a pickup of a baler comprises a flow rate sensor, a processing element, and a tractor speed controller. The flow rate sensor senses a flow rate of a crop into the pickup and outputs a flow rate signal with a level that varies according to the flow rate of the crop into the pickup. The processing element receives the flow rate signal, receives a speed signal regarding a speed of a tractor pulling the baler, compares the flow rate from the flow rate signal with the speed from the speed signal to generate a comparison result, and outputs an electronic speed signal with a level that varies according to the comparison result. The tractor speed controller is configured to receive the speed signal and adjust a speed of the tractor according to the level of the speed signal.