I have seen in a remote hilly place some people used a root of a plant{ ginger like shape} for bisecting a hilly stream with the help of a rope(touching the root throughout rope}.resulting blocking of water flow,thus making the down stream dry & started catching fish.what property of the root can do so is my curiosity.if anybody can explain the matter then iwill remain grateful to him. My e-mail :rizwanul232@gmail.com