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
Sorbus aucuparia at elevations of up to 2000 m. "S. aucuparia" appears north of the boreal forest at the arctic tree line; in Norway, it is found up to the 71st parallel north. It has naturalized in America from Washington to Alaska and eastward in Canada and the northeast of the US very successfully. "Sorbus aucuparia" is an undemanding species and can withstand shade. It is frost hardy and can tolerate winter dryness and a brief growing season. The plant is also resistant to air pollution, wind, and snow pressure. "S. aucuparia" mostly grows on soil that is moderately dry to moderately