Triffid

The Triffids appeared in the 1951 literature and the 1962 movie called The Day of the Triffids. Triffids are tall, carnivorous, mobile plants capable of aggressive and seemingly intelligent behaviour. They are able to move about by "walking" on their roots, appear to communicate with each other, and possess a deadly whip-like poisonous sting that enables them to kill their victims and feed on their rotting carcasses and they're only weakness is salt water.