Mountain Ash
Mountain Ash, a small ornamental tree of North America, Europe, and Asia. It is not a true ash. The tree grows 20 to 40 feet (6–12 m) tall. Each leaf consists of 11 to 17 narrow leaflets. The small white flowers are followed by clusters of red berries. The American mountain ash grows mainly in eastern Canada, New England, and the Great Lakes region. The European mountain ash, or rowan tree, is sometimes cultivated in the United States. Several species of true ash trees (genus Fraxinus) are popularly called mountain ash. They are large trees with leaves like those of the mountain ash but with winged seeds instead of berries.
The American mountain ash is Sorbus americana; European, S. aucuparia. Both belong to the rose family, Rosaceae.