Physocarpus capitatus (Pursh) Kuntze
Pacific ninebark
Rosaceae (Rose family)

Introduction to Vascular Plants

Photograph

© Province of British Columbia (Bill Jex)     (Photo ID #3393)


Map

E-Flora BC Static Map

Distribution of Physocarpus capitatus
Click here to view the full interactive map and legend

Species Information

General:
Medium to tall shrub, 1-4 m tall; branches erect to arching, angled, smooth to minutely star-shaped-hairy when young, eventually with brown, shredding bark.
Leaves:
Alternate, deciduous, the stalks 1-3 cm long, the blades egg- to heart-shaped in outline, 3-10 cm long, palmately 3- or 5-lobed, the lobes irregularly double-toothed, deeply veined, shiny dark green above, paler and with abundant star-shaped hairs below.
Flowers:
Inflorescences dense, terminal, half-rounded clusters of numerous stalked flowers, the stalks woolly; corollas white, saucer-shaped, the petals 5, nearly circular, 3-5 mm long; calyces densely star-shaped-hairy, 5-lobed, the lanceolate lobes about 3 mm long, somewhat bent back; ovaries superior; stamens about 30, pink.
Fruits:
Follicles, 3 to 5, barely joined at the base, inflated, 7-11 mm long, reddish, mostly smooth; seeds 1 to 4 per follicle, pear-shaped, yellowish, hardened, shiny.

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:
Late Spring
Fruit/Seed characteristics:
Colour: Red
Present over the Summer
Source:  The USDA

Ecology

Ecological Framework for Physocarpus capitatus

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)
223 0 1325
Slope Gradient (%)
6 0 90

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

274 35 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
5 0 7
Modal Nutrient Regime
Class
D
# of field plots
 species was recorded in:
96
Modal BEC Zone Class
CWH

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

CDF(13), CWH(66), ICH(4), IDF(3), PP(2)

Habitat and Range

Moist to wet streamside thickets, forest edges, open forests, margins of lakes and marshes, clearings and roadsides in the lowland to montane zones; frequent in SW BC, locally frequent in SE BC; N to AK and S to N ID and CA.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Physocarpus opulifolius (L.) Maxim., orth. cons.
Physocarpus opulifolius var. tomentellus (Ser.) B. Boivin

Taxonomic Notes

Dwarf Pacific Ninebark

Pacific ninebark is a large shrub frequently reaching four meters in height, but the dwarf mutant grows to be only about one-half meter in height, with horizontal spreading branches. Such dwarf mutants may involve a mutation affecting the normal growth hormones in the plant, or they could affect some biosynthetic pathway that is necessary for normal growth. Despite its small size, the mutant produces normal leaves and flowers.

Source: Extracted from Griffiths and Ganders, 1983, Wildflower Genetics: A Field Guide for British Columbia and the Northwest.

References

Griffiths, Anthony J. F. and Fred R. Ganders. 1983. Wildflower Genetics: A Field Guide for British Columbia and the Pacific Northwest. Flight Press, Vancouver.