Sorbus scopulina Greene
western mountain-ash (Greene's mountain ash)
Rosaceae (Rose family)

Introduction to Vascular Plants

Photograph

© Jamie Fenneman     (Photo ID #19750)


Map

E-Flora BC Static Map

Distribution of Sorbus scopulina
Click here to view the full interactive map and legend

Species Information

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.

SourceThe Illustrated Flora of British Columbia

Illustration

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

USDA Species Characteristics

Flower Colour:
White
Blooming Period:
Summer
Fruit/Seed characteristics:
Colour: Red
Present from Summer to Fall
Source:  The USDA

Ecology

Ecological Framework for Sorbus scopulina

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class

Avg

Min

Max

Elevation (metres)
1086 6 2750
Slope Gradient (%)
21 0 230

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

188 0 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
3 0 8
Modal Nutrient Regime
Class
C
# of field plots
 species was recorded in:
3892
Modal BEC Zone Class
SBS

All BEC Zones (# of stations/zone) species was recorded in

AT(1), BG(1), BWBS(129), CMA(1), CWH(109), ESSF(1108), ICH(811), IDF(52), MH(31), MS(168), PP(3), SBPS(28), SBS(1225), SWB(6)

Habitat and Range

Mesic to moist glades, streambanks, forest edges and open forests in the montane and subalpine zones; frequent throughout BC, except rare W of Coast-Cascade Mountains; N to AK, E to AB and S to ND, WY, NM and N CA.

SourceThe Illustrated Flora of British Columbia