E-Flora BC: Electronic Atlas of the Flora of British Columbia

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

Introduction to Vascular Plants

© Virginia Skilton  Email the photographer   (Photo ID #26239)

E-Flora BC Static Map
Distribution of Cirsium hookerianum
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Species Information

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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.

Source: The Illustrated Flora of British Columbia

Habitat / 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.

Source: The Illustrated Flora of British Columbia


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) 500 1640 2563
Slope Gradient (%) 0 41 100
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
29 160 350
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
0 2 6
Modal Nutrient Regime
Number 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)


The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is not evaluated, unknown or variable.

Taxonomic and Nomenclatural Links

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General References