A data processor can estimate a series of center points between the first row and the second row based on targeting substantial symmetry in the first sensor signal response and the second sensor signal response. A nozzle is associated with the sprayer implement. The nozzle has a nozzle position with respect to a corresponding center point between the rows of plants. An offset module is adapted to shift laterally the nozzle position from or with respect to each center point to a corresponding offset lateral position such that a spray pattern of the nozzle is directed toward target strip of soil or ground around or containing a plant stem, or root zone, of the plants in the row.