Showy mountain ash

Description

Sorbus decora, commonly known as the northern mountain ash, showy mountain-ash, or dogberry, is a deciduous shrub or very small tree native to northeastern North America. It occurs throughout the Laurentian Mixed Forest Province, the New England-Acadian forest region, and the eastern Canadian boreal forests. Showy mountain-ash grows 4–10 metres (13–33 ft) tall. Its leaves are odd-pinnately compound, with 11–17 leaflets. Each leaflet is 5–10 cm (2–4 in) long and 1–2.5 cm (3⁄8–1 in) wide. All parts are hairless to slightly hairy. Flowers are borne in 125- to more than 400-flowered panicles 6–25 cm (2+1⁄4–9+3⁄4 in) across. Each flower is 5–7.5 mm (1⁄4–1⁄4 in) across and has five white petals 2.5–3.5 mm (3⁄32–1⁄8 in) long, 14–20 stamens, and carpels with 3–4 styles. The fruits (pomes) are bright red to orange-red and 4–7 mm (5⁄32–9⁄32 in) across. Showy mountain-ash is very similar to the closely related American mountain-ash (Sorbus americana). Like the American mountain-ash, the showy mountain-ash has odd-pinnately compound leaves and often large clusters of flowers and fruits. Showy mountain-ash can be distinguished by its shiny, sticky buds, and its slightly larger flowers and fruit. It is said to bloom a week earlier. It is often cultivated as an ornamental plant for its cold-hardiness, its attractive flowers, and its large clusters of small red berry-like pomes. The fruits are an important source of food for wildlife, particularly birds in the winter and early spring. Sorbus is a genus of over 100 species of trees and shrubs in the rose family, Rosaceae. Species of Sorbus are commonly known as whitebeam, rowan (mountain-ash) and service tree. The exact number of species is disputed depending on the circumscription of the genus, and also due to the number of apomictic microspecies, which some treat as distinct species, but others group in a smaller number of variable species. Recent treatments classify Sorbus in a narrower sense to include only the pinnate leaved species of subgenus Sorbus, raising several of the other subgenera to generic rank. Sorbus is not closely related to the true ash trees which belong to the genus Fraxinus, although the leaves are superficially similar.