''Sorbus'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of over 100

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of trees and shrubs in the rose

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Rosaceae Rosaceae (), the rose family, is a family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus '' Rosa''. The family includes herbs, shrubs, and trees. Most species are deciduous, but som ...

. Species of ''Sorbus'' ('' s.str.'') are commonly known as

rowan The rowans ( or ) or mountain-ashes are shrubs or trees in the genus ''Sorbus'' of the rose family, Rosaceae. They are native throughout the cool temperate regions of the Northern Hemisphere, with the highest species diversity in the Himalaya ...

or mountain-ash. The genus used to include species commonly known as

whitebeam The whitebeams are members of the family Rosaceae, tribe Malinae, comprising a number of deciduous simple or lobe-leaved species formerly lumped together within ''Sorbus'' s.l. Many whitebeams are the result of extensive intergeneric hybridisa ...

, chequer tree and

service tree Service tree can refer to: * ''Sorbus domestica'', service tree or sorb tree * ''Sorbus latifolia'', service tree of Fontainebleau * ''Sorbus pseudofennica'', Arran service tree * ''Torminalis glaberrima'', wild service tree See also

* Service ...

that are now classified in other genera (see below). The genus ''Sorbus'', as currently circumscribed, includes only the

pinnate Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and ...

leaved species of former

subgenus In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...

''Sorbus''. ''Sorbus'' is not closely related to the true ash trees which belong to the genus ''

Fraxinus ''Fraxinus'' (), commonly called ash, is a genus of plants in the olive and lilac family, Oleaceae, and comprises 45–65 species of usually medium-to-large trees, most of which are deciduous trees, although some Subtropics, subtropical specie ...

'', although the leaves are superficially similar.

Genus

As treated in its broad sense, the genus was traditionally divided into several subgenera, however, this treatment was found to be

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

, comprising two disparate lineages within the Malinae subtribe. Consequently, each of the former subgenera have since been elevated into genera in their own right, with the genus name ''Sorbus'' retained only for the rowans. Additionally, it was recognised that despite a comparably large genetic distance between them, the genera ''Sorbus (''sensu stricto), ''Aria, Chamaemespilus'' and ''Torminalis'' have interbred extensively, in various combinations, which lead to the recognition of an additional five

intergeneric hybrid In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two dif ...

genera.Rushforth, Keith (2018)
The Whitebeam problem, and a solution.
''Phytologia'' 100(4): 222-247. 21 December 2018. ;''Sorbus'' (''Sorbus'') * now genus ''

Sorbus ''Sorbus'' is a genus of over 100 species of trees and shrubs in the rose family, Rosaceae. Species of ''Sorbus'' ('' s.str.'') are commonly known as rowan or mountain-ash. The genus used to include species commonly known as whitebeam, cheque ...

'' s.s., are commonly known as the rowan (primarily in the UK) or mountain-ash (in Ireland, North America and the UK), with compound leaves usually hairless or thinly hairy below; fruit carpels not fused; the

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

is ''

Sorbus aucuparia ''Sorbus aucuparia'', commonly called rowan (, also ) and mountain-ash, is a species of deciduous tree or shrub in the rose family. The tree has a slender trunk with smooth bark, a loose and roundish crown, and its leaves are pinnate in pairs o ...

'' (European rowan). Distribution: cool-temperate

Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined by humans as being in the same celestial sphere, celestial hemisphere relative to the invariable plane of the Solar ...

. ;''Sorbus'' (''Aria'') * now genus ''

Aria In music, an aria (, ; : , ; ''arias'' in common usage; diminutive form: arietta, ; : ariette; in English simply air (music), air) is a self-contained piece for one voice, with or without instrument (music), instrumental or orchestral accompan ...

'' and its intergeneric hybrids (see below), the whitebeams, with simple leaves usually strongly white-hairy below (hence the name, from German ''Weissbaum'', 'white tree'); fruit carpels not fused; the type is ''

Aria edulis ''Aria edulis'', the whitebeam or common whitebeam, is a species of deciduous tree in the family ''Rosaceae''. The tree often forms new shoots around the trunk. Typically compact and domed, the plant has a few upswept branches and the leaves ha ...

'' (common whitebeam). Distribution: Europe,

Maghreb The Maghreb (; ), also known as the Arab Maghreb () and Northwest Africa, is the western part of the Arab world. The region comprises western and central North Africa, including Algeria, Libya, Mauritania, Morocco, and Tunisia. The Maghreb al ...

and western Asia. ;''Sorbus'' (''Micromeles'') * now genus '' Micromeles'', a group of east Asian species with narrow leaves; sometimes previously included in subgenus ''Aria''. Distribution: temperate and tropical east Asia. ;''Sorbus'' (''Cormus'') * now genus ''Cormus'', with compound leaves similar to subgenus ''Sorbus'', but with distinct fused carpels in the fruit; just one species, ''

Cormus domestica ''Cormus domestica'', commonly known as service tree or sorb tree, is a species of tree native to western, central and southern Europe, northwest Africa (Atlas Mountains), and southwest Asia (east to the Caucasus).Rushforth, K. (1999). ''Trees ...

'' (true service tree). Distribution: North Africa, warm-temperate Europe, western Asia. Used to flavour some apple wines, see ''

Apfelwein ''Apfelwein'' (; ), or ''Viez'' (, Moselfranken, Saarland, Trier; ) or ''Most'' (, Austria, Switzerland, South Germany; ) are German words for cider. It is made from various kinds of sour tasting apples (such as "Bohnapfel"). It has an alcoho ...

''. ;''Sorbus'' (''Torminaria'') * now genus ''

Torminalis ''Torminalis'' is a genus of plants in the rose family, Rosaceae. The genus was formerly included within the genus ''Sorbus'' as the section ''Torminaria'', but the simple-leafed species traditionally classified in ''Sorbus'' are now considered ...

'', with rather maple-like lobed leaves with ''pointed'' lobes; fruit carpels not fused; just one species (wild service tree). Distribution: warm-temperate Europe, south to the mountains of North Africa and east to the

Caucasus The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, i ...

and

Lebanon Lebanon, officially the Republic of Lebanon, is a country in the Levant region of West Asia. Situated at the crossroads of the Mediterranean Basin and the Arabian Peninsula, it is bordered by Syria to the north and east, Israel to the south ...

ranges. ;''Sorbus'' (''Chamaemespilus'') * now genus ''

Chamaemespilus ''Chamaemespilus'' is a genus of shrubs in the family Rosaceae. It is monotypic, being represented by the single species ''Chamaemespilus alpina'', commonly known as false medlar or dwarf whitebeam. It is native to the mountains of central and so ...

'', monotypic, with a single shrubby species, false medlar. Has simple, glabrous leaves and pink flowers with erect sepals and petals. Distribution: mountains of southern Europe. Intergeneric hybrid genera * ''

Hedlundia ''Hedlundia'' is a genus of plants in the rose family (biology), family (of Rosaceae). They are shrubs or small trees that have a Hybrid (biology), hybrid origin involving crosses between ''Whitebeam, Aria'' and ''Sorbus'' sensu stricto. There ar ...

- Aria × Sorbus'' hybrids * ''

Karpatiosorbus ''Karpatiosorbus'' (Synonymy: ''Sorbus'' subgenus ''Tormaria'' Májovsky & Bernátová = ''S''. subgenus ''Aria'' x subgenus ''Torminaria'') is a genus of flowering plants in the family Rosaceae, native to Europe, including Crimea, and Algeria. S ...

'' - ''Aria'' × ''Torminalis'' hybrids * ''

Majovskya ''Majovskya'' is a genus of flowering plants belonging to the family Rosaceae. They are shrubs or small trees, they appear to have arisen via hybridization events between the clades ''Aria'' (Pers.) Host and '' Chamaemespilus'' (L.) Crantz. It i ...

'' - ''Aria'' × ''Chamaemespilus'' hybrids * ''

Scandosorbus ''Scandosorbus'' is a genus of flowering plants in the rose family, Rosaceae. It includes two species of trees native to northern Europe. *'' Scandosorbus intermedia'' – Denmark, Norway, Sweden, Finland, Baltic states, Poland, and Germany *'' ...

'' - syn. ''Borkhausenia''; ''Aria'' × ''Sorbus'' × ''Torminalis'' hybrids * ''

Normeyera ''Normeyera'' is a genus of flowering plants in the rose family, Rosaceae. It includes nine species native to west-central Europe, ranging from France through Switzerland, Germany, Austria, and Czechoslovakia to Poland. They are distinguished fr ...

'' - ''Aria'' × ''Chamaemespilus'' × ''Sorbus'' hybrids

Uses

Ornamental trees

''Sorbus'' species are cultivated as ornamental trees for parks and gardens and as avenue trees, and have given rise to several

cultivars A cultivar is a kind of cultivated plant that people have selected for desired traits and which retains those traits when propagated. Methods used to propagate cultivars include division, root and stem cuttings, offsets, grafting, tissue cult ...

. The following, of mixed or uncertain parentage, have gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. It includes the full range of cultivated p ...

: * 'Eastern Promise' (purple autumn colour, pink berries) * 'Leonard Messel' named for Leonard Messel of

Nymans Nymans is an English garden to the east of the village of Handcross, and in the civil parish of Slaugham in West Sussex, England. The garden was developed, starting in the late nineteenth century, by three generations of the Messel family, and ...

in Sussex. (small tree to 4m, pink berries) * 'Wisley Gold' (yellow berries)

Gallery

File:Punetav pihlapuu.jpg, Red rowan File:Rowan in the garden of Eastern Siberia.jpg, Rowan in the garden of

Eastern Siberia Eastern Siberia is a part of Siberia that incorporates the territory located between the Yenisei River in the west and the Pacific Ocean divides in the east. Its area is equal to 7.2 million sq. km.Galina Samoylova (Г. С. Самойлова)В� ...

Lijsterbes (Sorbus). 31-03-2024 (d.j.b.) 02.jpg, New leaf from one ''Sorbus'' opens up.

Genus

Uses

Ornamental trees

Gallery

References

Further reading