Crepis occidentalis subsp. costata Nutt. (A. Gray) Babc. & Stebbins
western hawksbeard (largeflower hawksbeard)
Asteraceae (Aster family)

Introduction to Vascular Plants

Photograph

© Chris Sears     (Photo ID #8786)


Map

E-Flora BC Static Map

Distribution of Crepis occidentalis subsp. costata
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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

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.

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. costata Gray
Psilochenia occidentalis subsp. costata (Gray) W.A. Weber