Centaurea cyanus L.
cornflower (bachelor's-button; garden cornflower)
Asteraceae (Aster family)

Introduction to Vascular Plants

Photograph

© Stephanie Rivest     (Photo ID #88495)


Map

E-Flora BC Static Map

Distribution of Centaurea cyanus
Click here to view the full interactive map and legend

Species Information

General:
Annual herb from a taproot; stems erect, branched, loosely hairy, 0.2-1.2 m tall.
Leaves:
Basal leaves linear to lanceolate, entire or with a few teeth and narrow lobes towards the base, white-woolly below, up to 13 cm long and 1 cm wide, soon deciduous; stem leaves similar, reduced and narrower upwards.
Flowers:
Heads discoid, several to many, solitary at the ends of ascending branches; disk flowers usually blue, sometimes purple, pink or white, the sterile marginal ones about 18 mm long, enlarged apically with 5 lobes, the central ones perfect and about 15 mm long; involucres 20-25 mm tall, 12-15 mm wide; involucral bracts egg-shaped or lanceolate, grooved, with a darkened, tattered fringe at the tips, glabrous.
Fruits:
Achenes compressed, with appressed, soft hairs, 3.5-4 mm long; pappus of numerous, strongly graduated brown bristles.

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.

Ecology

Ecological Framework for Centaurea cyanus

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)
745 745 745
Slope Gradient (%)
52 52 52

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

149 150 150
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
2 2 2
Modal Nutrient Regime
Class
C
# of field plots
 species was recorded in:
1
Modal BEC Zone Class
ICH

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

ICH(1)

Habitat and Range

Dry roadsides in the lowland and montane zones; infrequent in S BC; introduced from the Mediterranean region.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Leucacantha cyanus (L.) Nieuwl. & Lunell