No, farmers aren't being replaced with robots, but California growers can soon take advantage of the latest in video and computer technology to control weeds without using chemical pesticides. David C. Slaughter, an associate professor of biological and agricultural engineering at UC Davis, has developed a robotic, vision-guided vegetable cultivator. Video cameras mounted on the frame of the cultivator capture a ground-level view of the crop row, with 10 pictures taken per second. Those images are instantaneously flashed to the tractor's computer, which automatically centers the disc or other cultivating tools to cut out all weeds within one-third inch of the crop. During a recent nighttime field presentation, Slaughter demonstrated the cultivator's ability to work at night with lights illuminating the row for the camera's benefit. This night-time capability allows farmers the option of running the cultivator for three shifts in a 24-hour period, increasing the efficiency of the operation.