Rowan Rowan The rowans 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 mountains of western China and the Himalaya, where numerous apomictic microspecies occur. The name "rowan" was originally applied to the species "Sorbus aucuparia" and is also used for other species in "Sorbus" subgenus "Sorbus". Formerly, when a wider variety of fruits were commonly eaten in Europe and North America, "Sorbus" was a domestically used fruit throughout these regions. It is still used in
Arran whitebeams between "S. arranensis" and the mountain ash ("S. aucuparia"). The "Sorbus" group are apomictic, producing viable seed without the need for pollination and fertilisation. Each time this hybrid cross occurs a new clone is effectively produced. Smart showed by using physical characteristics that the species were separate and not a result of random variation. Some overlap does however occur and this suggests that some hybridising may occur between the two species. A number of other "Sorbus" species have been produced in this way, such as the Devon whitebeam, the Bristol whitebeam, the Cheddar whitebeam, Irish whitebeam, Lancaster whitebeam, etc. All