Purshia tridentata (Pursh) DC.
antelope-brush (antelope bitterbrush; bitter-brush)
Rosaceae (Rose family)

Introduction to Vascular Plants

Photograph

© Mike Edley     (Photo ID #3481)


Map

E-Flora BC Static Map

Distribution of Purshia tridentata
Click here to view the full interactive map and legend

Species Information

General:
Medium to tall shrub, 1-2 (3) m tall; stems erect, freely and rigidly branched, twigs woolly-hairy, especially when young.
Leaves:
Alternate, deciduous, in small bundles on short lateral spur-shoots, wedge-shaped, mostly 1-2 cm long, 3-toothed at the tip, silvery-greenish and hairy on the upper surface, grey-woolly beneath, the margins rolled under.
Flowers:
Inflorescence of single, short-stalked flowers at ends of short, lateral, leafy spur-shoots; corollas yellow to cream, wheel-shaped, the petals 5, egg- to spoon-shaped, 5-9 mm long, early-deciduous; calyces bell-shaped, woolly- or cobwebby-hairy and stalked-glandular, 5-lobed, the lobes oblong-egg-shaped, 3-4 mm long; ovaries superior; stamens about 25.
Fruits:
Large achenes, about 15 mm long including the persistent style, ellipsoid-spindle-shaped, somewhat leathery, velvety-hairy and glandular; seeds 1, black, pear-shaped, 6-8 mm long.

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:
Early Spring
Fruit/Seed characteristics:
Colour: Brown
Present from Spring to Summer
Source:  The USDA

Ecology

Ecological Framework for Purshia tridentata

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)
727 280 1540
Slope Gradient (%)
21 0 202

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

215 0 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
2 0 5
Modal Nutrient Regime
Class
C
# of field plots
 species was recorded in:
358
Modal BEC Zone Class
PP

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

BG(88), IDF(99), MS(2), PP(166)

Habitat and Range

Dry open slopes, grasslands and sagebrush shrublands in the steppe and adjoining lower montane zones; common in extreme S BC, east of the Coast-Cascade Mountains and south of about 51degreeN; S to MT, WY, CO, NM and CA.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Purshia tridentata var. tridentata