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SummarySorbus aria, COMMON WHITEBEAM, is described and illustrated. It is morphologically and genetically variable, and numerous selected forms are planted. Notes on its role as a parent of hybridogenous species and its historical and potential use are provided.

SummarySorbus cuneifolia, LLANGOLLEN WHITEBEAM, is described and illustrated. Details relating to its recognition as a distinct species are provided.

SummarySorbus rupicola, ROCK WHITEBEAM, is described and illustrated. It is one of the most widespread apomictic polyploids in the genus. Its origin within Sorbus subgenus Aria is still not clear, but it is an important parent of hybridogenic taxa throughout its range. Notes on propagation and cultivation are also included.

SummarySorbus torminalis (WILD SERVICE TREE) is described and illustrated. It is a species relatively isolated from its relatives, but its role as a parental taxon of hybridogenic species is noted. Notes on usage, cultivation and propagation are included.

SummarySorbus eminens, ROUND‐LEAVED WHITEBEAM is a tetraploid member of Sorbus subgenus Aria. The complex taxonomic history is summarised. This species is characterised by the large, unlobed, roundish leaves (sometimes likened in shape to a tennis ball) with rounded bases and few veins and usually acuminate, outwardly directed teeth, and large red fruits which are wider than long.

SummarySorbus aucuparia subsp. aucuparia, ROWAN or MOUNTAIN ASH, is described and illustrated. Details of its distribution, genetic variability, cultural history and use by humans and animals are provided.

SummarySorbus porrigentiformis, GREY‐LEAVED WHITEBEAM, is described and illustrated. It is a neoendemic with obovate leaves and fruits wider than long, and it is widespread in south‐west England and South Wales. It was originally broadly circumscribed, but it has now been split into at least 11 constituent parts. It is a cornerstone species for Sorbus speciation in Britain. It may have originated from S. aria × S. rupicola or from an ancestral taxon in Central Europe.

SummarySorbus subcuneata, SOMERSET WHITEBEAM, is described and illustrated. This narrow endemic species from coastal Devon and Somerset is endangered. Details of its discovery, historical taxonomic treatment and reproductive biology are provided.

SummarySorbus cambrensis, WELSH WHITEBEAM, is described and illustrated. It is a member of Sorbus subgenus Aria and is unusual in being a pentaploid. It is endemic to six sites in the eastern Brecon Beacons, Wales, and is 'Endangered.' It was first noted as a 'large‐leaved S. porrigentiformis' in the 1970s and was described in 2009. It is closely related to another pentaploid, S. stenophylla, both of which may be derived from hybridisation between S. rupicola and unknown members of Sorbus subgenus Aria.

SummarySorbus avonensis, AVON WHITEBEAM, is described and illustrated. It was originally treated as a triploid hybrid to cover plants of S. aria (diploid) × S. porrigentiformis (tetraploid) parentage, but after the discovery of more identical trees in 2014–2016, it is now treated as a species. It is endemic to the Avon Gorge, England where a population of c. 47 trees is known.

SummarySorbus bristoliensis, BRISTOL WHITEBEAM, is described and illustrated. The history of the discovery and the origin of this narrow endemic are discussed. Notes on propagation and cultivation are also included.