Lettuce Bot is a robotic terminator, targeting and selectively killing weeds on sight with 98 percent accuracy. It works by first differentiating weed from lettuce through its vision algorithms and then a trailing component either slices the weed down, injects a minimal dose of herbicide, or hits it with potent fertilizer. The fertilizer offers the best of both worlds in that it is concentrated enough to burn the weed’s roots but not so much to kill the lettuce — plus it provides extra nutrients to the soil.