Many cultures have stories of talking trees that give advice as well as warnings to people. Alexander the Great and Marco Polo were said to have visited such a tree in India. New research has found something amazing: it seems that plants can communicate. 

It has been known for some time that plants use chemicals to communicate with each other. This happens when a plant gets attacked by insects. The plant gives out chemicals from the leaves that are being eaten. This is like a warning, or a call for help. When another plant gets the chemicals, it starts to give out its own, different chemicals. Scientists hope to learn more about this plant warning system, so that we can use it to grow more crops. 

More surprisingly, plants also use sound to communicate. People can't hear these sounds, but plants are making them. Some plants make noises with their roots. Some trees make clicking noises when there is not enough water. 

Most surprisingly of all, plants have an amazing system of communication that can link nearly every plant in a forest. Scientists call this system the "wood wide web", which is linked underground by fungi(菌类). It links the roots of different plants to each other. It is in some ways similar to the Internet we use. Using the wood wide web, plants can share information and even food with each other. However, it may lead to bad effects. Plants may use it to steal food from each other, or spread chemicals to attack other plants.

Scientists are learning more every day about the secret ways in which plants talk to each other. Who knows? Maybe one day we will know enough about plant communication to be able to talk with them ourselves.