Centaurea diffusa Lam.
diffuse knapweed
Asteraceae (Aster family)
Introduction to Vascular Plants
diffuse knapweed
Asteraceae (Aster family)
Introduction to Vascular Plants
Species Information
General:
Annual, biennial or short-lived perennial herb from a taproot; stems erect, branched, sparsely hairy, 10-60 cm tall.
Leaves:
Basal leaves pinnately divided into linear segments, broadly lanceolate in outline, 3.5-20 cm long, 0.5-3.5 cm wide, grey-green, lightly dense-hairy, soon deciduous; stem leaves similar, reduced upwards.
Flowers:
Heads discoid, numerous, solitary at the end of diffuse branches; disk flowers usually creamish, sometimes purplish or pinkish; involucres 8-10 mm tall; involucral bracts broadly lanceolate, leathery, glabrous, with weak spines on the margins, the tips with 1.5-4 mm long spines.
Fruits:
Achenes glabrous; pappus lacking or of minute bristles up to 1 mm long.
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.
Illustration Source: The Illustrated Flora of British Columbia
Ecology
Ecological Framework for Centaurea diffusa
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)
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) |
603 | 260 | 1772 |
| Slope
Gradient (%) |
23 | 0 | 80 |
|
Aspect (degrees) |
204 | 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: |
214 | ||
| Modal
BEC Zone Class |
PP | ||
|
All BEC Zones (# of stations/zone) species was recorded in |
BG(62), ICH(9), IDF(58), PP(75) | ||
|
Source:
Klinkenberg 2013
|
|||
Habitat and Range
Dry roadsides, disturbed areas, overgrazed grasslands and shrublands in the steppe and lower montane zones; common in S BC east of the Coast-Cascade Mountains; introduced from the E Mediterranean region.Status Information
Synonyms
Synonyms and Alternate Names:
Acosta diffusa (Lam.) Soják