For researchers and graduates with any interest in plant or soil sciences, this fascinating study will be a godsend ¿ it¿s the complete state of the art with regard to actinorhizal symbioses. The self-contained sixth volume of a comprehensive series on nitrogen fixation, it includes chapters that deal with all aspects of this symbiosis between actinorhizal plants and nitrogen-fixing bacteria. It also contains information both about symbionts and their ecological role and use. Other chapters tackle the global distribution of different actinorhizal plants and their microsymbionts and how this impacts the question of co-evolution of the micro- and macrosymbionts as well as comparing the actinorhizal and