FIELD MARKER CONTROL SYSTEM FOR AGRICULTURAL PLANTERS

A control system is provided for automatically deploying the field markers on an agricultural planter in an alternating manner without requiring operator input. The control system utilizes a proximity sensor to determine whether the tool bar is coming from the lowered working position to the raised headland position or vice versa. Solenoid valves in the hydraulic circuit to the field marker actuators are activated to retract both actuators to retract the deployed one of the field markers when the tool bar is moved into the headland position. When the tool bar is returned to the working position after making a turn at the field headlands, the control system remembers which field marker had just previously been deployed and then extends the other field marker to score the field. The control system permits the operator to remain attentive to the turning of the tractor and implement at the headlands and the setting of the planting implement into the ground at the proper location for planting the crop.