E-Flora BC: Electronic Atlas of the Flora of BC

Sorbus scopulina var. cascadensis Greene
western mountain-ash (Cascade mountain ash)
Rosaceae (Rose family)

Introduction to Vascular Plants

General:
Medium to tall shrub, 1-5 m tall; stems several, erect to spreading, freely branched, reddish-brown to yellowish; winter buds and young growth sticky, somewhat white- or grey-hairy.

Leaves:
Alternate, deciduous, pinnately compound; leaflets (7) 9 to 13, oblong-lanceolate to narrowly elliptic, 2-8 cm long, usually short-tapering to a sharp-pointed tip, smooth, finely saw-toothed almost to the base.

Flowers:
Inflorescence a flat-topped to somewhat rounded, branched cluster of numerous (70 to 200 or more) small flowers, the branches more or less white-hairy; corollas white to cream, the petals 5, oval, 4-6 mm long; calyces white-hairy, 5-lobed, the lobes triangular; ovaries inferior; stamens 15-20.

Fruits:
Berry-like pomes (like miniature apples), nearly globe-shaped, 7-10 mm long, orange to scarlet, not glaucous, 2- to 5-chambered; seeds 1 or 2 per chamber.

Notes:
Two varieties occur in BC:

1. Leaflets often 13; stipules usually shed before end of blooming; plants from E of Coast-Cascade Mountains................ var. scopulina

1. Leaflets rarely more than 11; stipules persistent until after blooming; plants from W slope of Cascade Mountains..................... var. cascadensis (G.N Jones) C.L. Hitchc.

Source: The Illustrated Flora of British Columbia

Origin Status	Provincial Status	BC List (Red Blue List)	COSEWIC
Native	S5	Yellow	Not Listed

BC Ministry of Environment: BC Species and Ecosystems Explorer.

1. Plants becoming trees over 5 m tall; leaflets usually more than 13, winter buds covered with long soft-hairy grey hairs; styles 2 or 3...........................S. aucuparia

1. Plants shrubby, usually less than 5 m tall; leaflets rarely as many as 13, winter buds not covered with long soft grey hairs; styles 3 to 5.

2. Winter buds rusty-hairy; calyces smooth on outside; leaflets blunt or rounded at the tip, toothed for not more than 3/4 of their length; styles 4 or 5, fruit red, glaucous...............S. sitchensis

2. Winter buds sticky, sparsely white-hairy; calyces hairy on outside; leaflets sharp-pointed at tip, toothed for most of their length; styles 3 or 4; fruit orange, not glaucous................S. scopulina

Source: Illustrated Flora of British Columbia

Photograph click to collapse contents

Map click to expand contents

Species Information click to expand contents

Habitat and Range click to expand contents

Status Information click to expand contents

Taxonomic Keys click to expand contents

loading