Sorbus decora (Sarg.) C. K. Schneid. - Showy Mountain Ash


 

|  back  | forward |

Sorbus decora - (image 1 of 6)

 

Taxonomy

Family: Rosaceae

Habitat

Cool woods, rocky shores of rivers and lakes. Some of these were found above 3500' in the Catskills.

Associates

 

 Distribution

Most of eastern Canada. Sporadic in the US, restricted to northern New England and the northernmost parts of MN, WI, IN, MI, and OH.

Morphology

Woody shrub or small tree, to 15 m high but more typically 6-8 m, freely branching, crown short and rounded. Leaves pinnate compound, to 20 cm long, 13-17 leaflets, upper surface blue-green, paler beneath, slightly hairy when young; leaflets narrowly elliptic, to 8 cm long, scarcely tapered, abruptly acute, the terminal tooth distinctly prolonged-acuminate, margins with mostly singly serrate, sharply acuminate teeth. Buds conical, red-brown, shiny, sticky. Twigs glabrous, red-brown to graying. Bark smooth, thin, light gray green to golden-brown, becoming slightly scaly with age. Flowers creamy white, in dense, many-flowered, open clusters. Fruits shiny, red, 7-10 mm thick.

Notes

Flowers May and early June

Wetland indicator: Facultative Upland

This is a beautiful tree in several seasons but unfortunately it is not well adapted to suburban landscapes. Hardy to zones 2-5. It has probably been extirpated from IN and IL, although there is some question to its ever having been native to IL.

Images 3-5 are of a specimen at the Morton Arboretum that was labeled Sorbus americana. However, S. americana typically has leaflets that are more or less long-acuminate and mostly 3-5 times as long as wide in addition to fruit 4-7 mm thick, and these characteristic that do not seem to fit the specimen.

 

References

Farrar, J. L. 1995. Trees of the Northern United States and Canada.
Ames, Iowa: Iowa State University Press

 

Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. Second Ed.
The New York Botanical Garden. Bronx, NY

 

Swink, F. and G. Wilhelm. 1994. Plants of the Chicago Region.
Indiana Academy of Science. The Morton Arboretum. Lisle, Illinois.

 


Home

 

 Michael Hough 2005