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 × intermedia each side of the leaf, broadest near the middle, rounded at the apex, and finely serrated margins. The autumn colour is dull yellowish to grey-brown. The flowers are 15–20 mm diameter, with five white petals and 20 yellowish-white stamens; they are produced in corymbs 8–12 cm diameter in late spring. The fruit is an oval pome 15 mm long and 10 mm diameter, orange-red to red, maturing in mid autumn. The fruit is dryish, and eaten by thrushes and waxwings, which disperse the seeds. "Sorbus intermedia" is a triple hybrid between "S. aucuparia", "S. torminalis", and either "S. aria" or