Since its first publication in 1991, New Flora of the British Isles has become established as the standard work on the identification of the wild vascular plants of the British Isles. The Flora remains unique in many features, including its full coverage of all British wild plants, its user-friendly organisation, and its specially compiled keys and descriptions. This new edition includes the addition of more than 160 species, so that 4,800 taxa are now covered in varying degrees of detail. It also incorporates the new molecular system of classification based on DNA sequences. Furthermore, it includes 1600 species illustrations, rewritten distributions and an overhaul of the designation of degrees of rarity, with the introduction of a third, less rare, category. These revisions should ensure that this third edition remains the essential reference source for all taxonomists, ecologists, conservationists, plant hunters and biogeographers, whether they be researchers, teachers, students or amateurs.

"Since its first publication in 1991, New Flora of the British Isles has become established as the standard work on the identification of the wild flowering plants, ferns and conifers of the British Isles. The Flora remains unique in many features, including its full coverage of all our wild plants in one volume, it's user-friendly organisation, and its specially compiled keys and descriptions. All native, naturalised, crop and repeatedly occurring casual plants are included...More than 200 species and hybrids have been added to the text of this fourth edition, and, in order to establish it as a truly twenty-first century flora, alien species that have not been recorded in the British Isles since 1999 (about 90 taxa) are omitted from the main text. The third edition (2010) was the first British Flora to incorporate the new molecular system of classification based primarily on DNA sequences, a scheme that is expected to endure for centuries to come at the family level. However, new discoveries from this research are continually being made, necessitating numerous further changes, particularly at the genus level, which have been incorporated in this fourth edition."--Back cover.

Vascular plant hybrids are numerous and constitute an important feature of our vegetation, but all too often they have been neglected by botanists. Some hybrids between native species are rare, sterile and ephemeral, but others reproduce vegetatively or by seed and have spread beyond the areas where their parents coexist. In addition, numerous hybrids have escaped from gardens to become established in the wild. Interspecific hybridisation is particularly significant as it represents a major evolutionary pathway in flowering plants; frequently it alters the characteristics of both native and alien taxa and it generates new species. The hybrid flora of the British Isles has been studied in more detail than that of any other region, and it therefore provides an ideal opportunity to study the occurrence of hybrids in wild vegetation. This book provides detailed accounts of the 909 hybrids reliably recorded in the wild in the British Isles. Of particular interest to BSBI members are the comprehensive identification notes, including a summary of the differences from the parents, enabling naming and recording of hybrids to a degree not attainable previously. The habitats of the hybrids are outlined and detailed accounts of their distributions provided, with notes on the discovery of many hybrids. There are 388 novel maps illustrating the records of the commoner hybrids in relation to those of their parents. Known chromosome numbers are given for each hybrid and its parents, and information is provided on the hybrid's fertility/sterility and its capacity for vegetative reproduction. Experimental and molecular studies of the hybrids in the British Isles and elsewhere in their ranges are summarised. Briefer notes are given on a further 156 hybrids, including some which are erroneously or doubtfully recorded and others which might potentially occur as escapes from cultivation.

Following rigorous testing throughout Britain and Ireland over the last 10 years, this second edition is a much revised version with re-written keys, additional species, phenology and, of course, many new novel identification characters. A few new illustrations have been added where space allows. In addition, the nomenclature has been updated in line with modern taxonomy. Each key has been carefully reviewed and revamped so this version aims to be quicker and more comprehensive in detail than its predecessor, greatly improving on the original work. Additional floral and fruiting characters have been added for some of the more difficult species making it more handy for casual field use.

This book describes and illustrates in detail the 760 species of mosses currently known to occur in the British Isles and incorporates the most up-to-date information available on classification and nomenclature, together with recent synonyms. The species descriptions provide information on frequency, ecology, geographical relationships and distribution, including information on protected species and those species at risk. For many species there are footnotes to aid identification. In addition to the species descriptions there are descriptions of families and genera and also introductory information on conservation, collection, preservation and examination of material, together with advice on using the keys. An artificial key to genera provides the only workable comprehensive key published in the English language. This second edition incorporates the very considerable advances in our knowledge of mosses made in the last quarter of the twentieth century and will provide a unique resource for all concerned with these fascinating organisms.

Detailed guide to identification for botanists and students.