The rowans or mountain-ashes are shrubs or small trees. 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.Rushforth, K. (1999). Trees of Britain and Europe. Collins ISBN 0-00-220013-9. The name rowan was originally applied to the species Sorbus aucuparia. Etymology and other names The name "rowan" is derived from the Old Norse name fo… (More on Rowan)