Abstract: The present device relates to an agricultural chemical applicator for applying herbicides. The system is activated by a sensor bar having a plurality of conductive wire rod sensors. When a sensor contacts an unwanted plant, a detector and control circuit detects the current leakage and activates a time delay circuit which uses two timers in series and an opto-isolator to activate a solenoid valve. When a particular sensor is activated, a particular valve will be opened, thereby sending chemicals through a specific nozzle. Each sensor has its own circuit and its own nozzles.