Alien Plants (Collins New Naturalist Library, Book 129)The word aliens can be used in many ways, to invoke fear, dislike and fascination. For biologists it is used to indicate organisms that have been introduced by people to new territories. In the British Isles alien plants are common, conspicuous, pestiferous, beautiful, edible and can be both useful and harmful. Over the last fifty years, the study of alien plants has progressed from an eccentric hobby, enabling amateur botanists to increase the total