Cirsium hookerianum Nutt.
Hooker's thistle (white thistle)
Asteraceae (Aster family)

Introduction to Vascular Plants


© Virginia Skilton     (Photo ID #26239)


E-Flora BC Static Map

Distribution of Cirsium hookerianum
Click here to view the full interactive map and legend

Species Information

Biennial or short-lived perennial herb from a taproot; stems erect, thick, fleshy, ribbed, soft, sparsely long-hairy to short, curly-haired, 0.2-2.0 m tall.
Mainly basal, these narrowly oblanceolate, nearly entire or pinnately lobed to 1/2 the width of the blade, the segments triangular-lanceolate; stem leaves elliptic-oblong, clasping, up to 30 cm long and 3 cm wide, usually shallowly lobed, margins with a few, weak spines up to 5 mm long, lightly hairy above, densely woolly below.
Heads discoid, 1-6, in a terminal cluster; involucres short-bell-shaped, 2-3 cm tall; involucral bracts densely woolly, linear-lanceolate to lanceolate, not much graduated, middle and outer ones tapering to a slender 3-5 mm, yellow spine, inner ones abruptly sharp-pointed, unarmed, sometimes twisted at the tip; disk flowers white to creamy white, rarely pinkish, 20-26 mm long.
Achenes 5-6.5 mm long, brown with lighter parallel lines; pappus light yellow, 15-20 mm long, shorter than the corollas by 3-5 mm.

SourceThe Illustrated Flora of British Columbia


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.


Ecological Framework for Cirsium hookerianum

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




Elevation (metres)
1640 500 2563
Slope Gradient (%)
41 0 100

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

160 29 350
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
2 0 6
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

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

AT(10), BG(20), ESSF(70), ICH(2), IDF(14), MS(3)

Habitat and Range

Moist to mesic roadsides, meadows and forest openings in the steppe and montane zones; frequent in S BC east of the Coast-Cascade Mountains; E to AB and S to ID, NW MT and WA.

SourceThe Illustrated Flora of British Columbia