Sorbus arranensis rupicola") which is still found on Holy Isle. This hybrid species interbred with the rowan/mountain ash ("Sorbus aucuparia") to produce "S. arranesis". The bastard mountain ash ("Sorbus pseudofennica") arose from a further cross between "S. arranensis" and the mountain ash ("S. aucuparia"). 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. Sorbus arranensis Sorbus arranensis, sometimes referred to as the Scottish or Arran whitebeam is a species of plant in the family Rosaceae. It
Sorbus alnifolia Sorbus alnifolia Sorbus alnifolia (syn. "Aria alnifolia"), also called alder-leafed whitebeam, Korean whitebeam, or Korean mountain ash, , is a species of whitebeam native to eastern Asia in eastern and northern China, Taiwan, Korea and Japan. "Sorbus alnifolia" is a medium-sized deciduous tree growing to 10–20 m tall with a trunk up to 30 cm diameter and grey bark; the crown is columnar or conic in young trees, becoming rounded with age, with branches angled upwards, and slender shoots. The leaves are green above, and thinly hairy with white hairs beneath, 5–10 cm long and 3–6 cm broad, simple, usually