This dictionary is a reference work on all aspects of the study of plants. With more than 5000 entries, it should be valuable to students, amateur botanists and naturalists, and everyone with an interest in plants and their environments. Many of the entries have been taken from the Oxford Dictionary of Natural History, but each one has been scrutinized thoroughly and, where necessary, amended or rewritten to adapt it to the new dictionary. A substantial number of new entries have been added in the areas of ecology, plant physiology, biochemistry, cytology, and genetics, and other subjects covered include biogeography, evolution, Earth history and the Earth sciences. There are also brief biographical notes on some of the most eminent botanists of the past. The dictionary provides world-wide coverage of taxonomic groups and takes full account of recent taxonomical revisions. One-third of the entries are devoted to taxa, from bacteria and fungi to the main groups of flowering and non-flowering plants.