Crepis occidentalis Nutt.
western hawksbeard (largeflower hawksbeard; Western hawksbeard )
Asteraceae (Aster family)

Introduction to Vascular Plants

Photograph

© Chris Sears     (Photo ID #8785)


Map

E-Flora BC Static Map

Distribution of Crepis occidentalis
Click here to view the full interactive map and legend

Species Information

General:
Perennial herb from a taproot and stem-base; stems erect, 1-3, densely and closely grey-short woolly-hairy, or nearly glabrous in age, often glandular-stiff-hairy above, sometimes with black glandular bristles above, 5-40 cm tall.
Leaves:
Basal leaves long-stalked, toothed, with the teeth pointing backwards, or deeply pinnately cut with lanceolate or linear toothed lobes, these entire, abruptly sharp-pointed or with long-pointed tips, mostly 1-3.5 dm long, the blades grey-short woolly-hairy, or nearly glabrous in age; lower stem leaves similar to the basal leaves, becoming reduced, linear and entire upwards.
Flowers:
Heads with strap-shaped flowers, 2-25 in a flat-topped inflorescence; involucres 11-19 mm tall, cylindric or bell-shaped; involucral bracts grey, short woolly-hairy with or without gland-tipped hairs, the longest outer ones usually less than 1/2 as long as the inner, triangular or egg-shaped, abruptly sharp-pointed, rarely linear, the inner ones lanceolate, abruptly sharp-pointed or with long-pointed tips with membranous margins; ray flowers yellow, 16-19 mm long.
Fruits:
Achenes, light to dark brown, 6-10 mm long, spindle-shaped, 10- to 18-ribbed, only slightly tapering to a slender tip; pappus white to yellowish-white, of copious, soft, hairlike bristles.
Notes:
Three subspecies, sometimes difficult to separate, occur in BC.

1. Involucres with at least some gland-tipped hairs.

2. Largest heads 18- to 30-flowered, with 10-13 inner involucral bracts.................. ssp. occidentalis

2. Largest heads 12- to 14-flowered, with 8-9 inner involucral bracts....................... ssp. costata (A. Gray) Babc. & Stebb.

1. Involucres without gland-tipped hairs..................... ssp. pumila (Rydb.) Babc. & Stebb.

SourceThe Illustrated Flora of British Columbia

USDA Species Characteristics

Flower Colour:
Yellow
Blooming Period:
Late Spring
Fruit/Seed characteristics:
Colour: Brown
Present from Spring to Summer
Source:  The USDA

Ecology

Ecological Framework for Crepis occidentalis

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)
833 500 1050
Slope Gradient (%)
40 8 65

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

261 150 350
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
2 1 4
Modal Nutrient Regime
Class
C
# of field plots
 species was recorded in:
8
Modal BEC Zone Class
BG

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

BG(5), IDF(3)

Habitat and Range

Dry grasslands and shrublands in the steppe zone; all subspecies frequent (ssp. costata, ssp. occidentalis) or rare (ssp. pumila) in SC BC, frequent in SE BC (ssp. occidentalis); E to S AB and SD, S to NM and CA.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Crepis occidentalis var. nevadensis Kellogg p.p.
Crepis occidentalis var. nevadensis Kellogg
Psilochenia modocensis subsp. subacaulis (Kellogg) W.A. Weber
Psilochenia occidentalis subsp. conjuncta (Jeps.) W.A. Weber