Can trees talk? Yes—but not in words. Scientists have reasons to believe that trees do communicate with each other. Not long ago, researchers learned some surprising things. First a willow tree (柳树) attacked in the woods by caterpillars (毛毛虫) changed the chemistry of its leaves and made them tasteless so that the caterpillars got tired of the leaves and stopped eating them. And the tree sent out a special vapor—a signal causing its neighbors to change the chemistry of their own leaves and make themselves taste also terrible too.

    Talking, of course, doesn't need to be always in words. We can talk to each other by smiling, raising our shoulders and moving our hands. We know that birds use a whole vocabulary of songs, sounds and movements. Bees dance their signals, flying in certain patterns that tell other bees where to find nectar (花蜜) for honey. So why shouldn't trees have ways of sending messages?