1275 Sorbus americanaCommon Names: American mountain ash,mountain ash,roundwood; dogberry,missey-moosey,American rowan Family: Rosaceae (rose Family)
American mountain ash can be a small tree, getting 20-30 ft (6-9 m) tall, with an open, rounded canopy up to 25 ft (7 m) across. Or, it can be a shorter, multi-stemmed shrub. The deciduous, pinnately compound leaves are 6-10 in (15-25 cm) long and arranged alternately. The 11-17 leaflets are narrowly lance shaped, 2-4 in (5-10 cm) long, and have sharply toothed margins. They turn yellow or orange-red in fall, often providing breath-taking displays. The inflorescence in late spring or early summer is a dense cluster, 5-6 in (12-15 cm) across, of tiny 5-petaled white flowers. Fruits are attractive spherical bright scarlet-red or orange-red berrylike pomes, about a quarter inch (62 mm) in diameter, each with 5-10 seeds. 'Dwarfcrown', sometimes marketed as Red Cascade ™, is a cultivar that is smaller and has a more upright and narrow crown than the species.
Sorbus americana is native to northeastern North America, from Newfoundland to Manitoba, south to northern Michigan and Pennsylvania, and in the Appalachian Mountains as far south as extreme northeastern Georgia. In the far North, mountain ash grows in coniferous forests and in mixed woodlands, often alongside bogs and swamps. In the Appalachian Mountains it occurs mainly above 5000 ft (1500 m) MSL, sometimes on scree and rocky hillsides and often in spruce-fir forests. American mountain ash is an understory shrub or tree typically found in association with balsam fir (Abies balsamea), red spruce (Picea rubens), American yew (Taxus canadensis), mountain maple (Acer spicatum), yellow birch (Betula lutea), paper birch (B. papyrifera), northern red oak (Quercus rubra) and yellow buckeye (Aesculus flava).
Light: Grow mountain ash in light, dappled shade to full sun in the more northern parts of its suitable range. Moisture: Mountain ash likes a neutral to slightly acidic soil that is relatively moist, but well drained. They are at their best in cool, moist habitats. Hardiness: USDA Zones 2 - 7 . American mountain ash does not tolerate warm climates and is at its best where winters are very cold. Propagation: Harvest fruits as soon as ripe, otherwise the birds will probably get them. Extract seeds by macerating the fruits in water for several days, then picking out the floating seeds. They may be planted outside immediately, or dried for storage. Once dried, the seeds can be stored for several years, and then must be chilled for 60 days or more before they will germinate. Sow prechilled seeds outside in the fall. Greenwood cuttings may be rooted in spring, but results can be erratic.
American mountain ash tolerates air pollution and is sometimes used as a street tree, and is often planted in parks. This is an ideal specimen tree for the smaller landscape. Up North, mountain ash is a favorite small ornamental shade tree. The fall color is among the finest of trees, varying from yellow to red to purple.
The berries are edible but too acidic to be eaten raw; they are sometimes made into jelly and Native Americans cooked them. Native Americans also used decoctions of the inner bark, taken internally, for various medicinal purposes.
The vivid orange to red fruits can remain on the tree after leaf fall through late winter, providing valuable food for wintering birds, small mammals and the occasional black bear. The foliage is a preferred browse for moose and deer.
In late spring, mountain ashes in bloom on the high peaks of the Appalachians put on a fabulous display that is equaled only by the September display of their bright red fruits. Where I grew up in New York’s Adirondacks, we had one in our front yard that never failed to delight. The beautiful American mountain ash deserves to be more widely used in parks, along streets and in home landscapes wherever it will grow.
The raw fruits are said to cause mild stomach upset, but they are OK when cooked.
Steve Christman 12/11/16