Sorbus is a genus of over 100 species of trees and shrubs in the rose family, Rosaceae. Species of Sorbus (s.l.) are commonly known as whitebeam, rowan, mountain-ash and service tree. The exact number of species is disputed depending on the circumscription of the genus, and also due to the number of apomictic microspecies, which some treat as distinct species, but others group in a smaller number of variable species. Recent treatments classify Sorbus in a narrower sense to include only the pinnate leaved species of subgenus Sorbus, raising several of the other subgenera to generic rank.
The whitebeams are members of the family Rosaceae, comprising the genus Aria. They are deciduous trees with simple or lobed leaves, arranged alternately. They are related to the rowans, and many of the endemic restricted-range apomictic microspecies of whitebeam in Europe are thought to derive from hybrids between the common whitebeam and the European rowan. Some are also thought to be hybrids with the wild service tree, and the service tree of Fontainebleau found in French woodlands.
Karpatiosorbus latifolia is a species of whitebeam that is endemic to the area around Fontainebleau, south of Paris in France, where it has been known since the early eighteenth century.
The Arran whitebeams are species of whitebeam endemic to the island of Arran, Ayrshire, Scotland.
Hedlundia pseudomeinichii, known as false rowan and Catacol whitebeam, is a rare species of tree endemic to the Isle of Arran in south-western Scotland. It is believed to have arisen as a hybrid of the native European rowan and the cut-leaved whitebeam which is in turn a rowan/Arran whitebeam hybrid. Until 2020, only one living specimens of the Catacol whitebeam was known, at the time making it the rarest tree not only in Scotland, but joint rarest in the world with Wood's cycad. Another was recorded as a sapling, but is believed to have been destroyed by deer. A seedling and grafted plants have also been grown in Edinburgh.
Karpatiosorbus bristoliensis is a species of flowering plant in the family Rosaceae. It is known commonly as the Bristol whitebeam. It is endemic to Great Britain, growing wild only in the Avon Gorge and in the Leigh Woods area of Bristol. There are around 300 individuals as of 2016, and the population is thought to be increasing.
Aria eminens, commonly known as the round-leaved whitebeam, is a species of plant in the family Rosaceae. It is endemic to Great Britain and is threatened by habitat loss.
Aria × leptophylla, commonly known as the thin-leaved whitebeam, is a species of plant in the family Rosaceae. It is endemic to Wales. It is a hybrid between Aria edulis and Aria porrigentiformis.
Hedlundia pseudofennica, also called Arran service-tree or Arran cut-leaved whitebeam, is a species of plant in the family Rosaceae. Endemic to the Isle of Arran in Scotland, it is threatened by habitat loss. It is thought to be a naturally occurring hybrid between H. arranensis and Sorbus aucuparia, probably with additional backcrossing with S. aucuparia. Hedlundia arranensis is itself a hybrid between Aria rupicola and S. aucuparia. Apomixis and hybridization are common in some groups of Sorbus species.
Karpatiosorbus subcuneata, the Somerset whitebeam, is a species of plant in the family Rosaceae. It is endemic to coastal north Devon and west Somerset in the United Kingdom. It is threatened by habitat loss.
Aria vexans, commonly known as bloody whitebeam, is a rare species of tree in the family Rosaceae. It is endemic to England and is found along the coast between Culbone in Somerset and an area just west of Trentishoe in Devon. It can be seen in the Exmoor National Park. It is threatened by habitat loss.
Aria wilmottiana, commonly known as Willmott's whitebeam, is a species of whitebeam in the family Rosaceae. It is endemic to England, and is found in the Avon Gorge, in Somerset and Gloucestershire. It is threatened by habitat loss.
Scandosorbus intermedia or, formerly, Sorbus intermedia, the Swedish whitebeam, is a species of whitebeam found in southern Sweden, with scattered occurrences in Estonia, Latvia, easternmost Denmark (Bornholm), the far southwest of Finland, and northern Poland.
Hedlundia hybrida, the Swedish service-treeFinnish whitebeam, or oakleaf mountain ash, is a species of whitebeam native to Norway, eastern Sweden, south-western Finland, and locally in Latvia.
Cornwall is the county that forms the tip of the southwestern peninsula of England; this area has a mild and warm climate regulated by the Gulf Stream. The mild climate allows rich plant cover, such as palm trees in the far south and west of the county and in the Isles of Scilly, due to sub-tropical conditions in the summer.
Sorbus minima, commonly known as the lesser whitebeam or least whitebeam, is a shrub belonging to the subgenus Aria (whitebeams) in the genus Sorbus. It is endemic to Wales where it grows at a few sites in Breconshire. It is an apomictic microspecies which reproduces asexually and so is reproductively isolated from its close relatives such as the Swedish whitebeam, S. intermedia. It probably originated as a hybrid between the rock whitebeam and the rowan. It was first discovered in 1893 by Augustin Ley, the vicar of Sellack in Herefordshire who travelled widely in Wales.
Karpatiosorbus admonitor, previously classified as Sorbus admonitor and also called the no parking whitebeam, is a species of whitebeam tree found in Devon, United Kingdom. It is known only from the Watersmeet Valley at Lynton, with two stray plants growing on the coast above Sillery Sands, Countisbury.
Pyrus cordata, the Heart-leaved pear or Plymouth pear, is a rare wild species of pear belonging to the family Rosaceae. It gets its name in Spanish, Portuguese and French from the shape of its leaves. In the UK, it is known as Plymouth Pear after the city of Plymouth in Devon, where it was originally found in 1870 The Plymouth pear was one of the British trees to be funded under English Natures Species Recovery Programme.
Aria porrigentiformis, commonly known as the grey-leafed whitebeam, is a species of whitebeam endemic to England and Wales.
