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

Cirsium scariosum Nutt.
elk thistle
Asteraceae (Aster family)

Introduction to Vascular Plants
Once images have been obtained, photographs of this species will be displayed in this window.Click on the image to enter our photo gallery.
Currently no image is available for this taxon.
E-Flora BC Static Map
Distribution of Cirsium scariosum
Click here to view our interactive map and legend
Details about map content are available here
Click on the map dots to view record details.

Cirsium scariosum var. scariosum

Species Information

Click on the image below to view an expanded illustration for this species.

Biennial or perennial herb from a taproot; stems erect, thick, fleshy, ribbed, sparsely hairy, simple or with a few short upper branches, 0.2-1.0 m tall.
Basal leaves egg-shaped to elliptic, entire to nearly entire, stalked; lower stem leaves narrowly egg-shaped, tapering to the base, stalked, shallowly to pinnately lobed, marginally spiny with numerous, slender, yellow spines up to 10 mm long, lobed 1/2 or less the width of the blade, segments lanceolate to deltoid, green and nearly glabrous above, woolly-hairy below; the uppermost leaves narrower, ascending, extending beyond the compact group of heads.
Heads discoid, 5-15, in a terminal cluster or rarely at the ends of the few branches or in the leaf axils; involucres bell-shaped, 2-3 cm tall; involucral bracts without glands, essentially glabrous except for the sparse marginal hairs, outer ones egg-shaped to lanceolate, with a slender 2-4 mm long spine, inner ones unarmed, the tips membranous, often dilated, papery and irregularly-margined; disk flowers white to pink, 18-30 mm long, the tubes 9-13 mm long, the lobes 4-6 mm long.
Achenes 5.5-6.5 mm long, light or dark brown with a narrow, yellow apical band; pappus light yellow, 2-3 cm long, shorter than the corollas by 4-5 mm.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Dry open forests in the montane zone; rare in SE BC, known recently only from Crowsnest Pass and Akamina Creek; E to AB and S to ID, MT, CO and AZ.

Source: The Illustrated Flora of British Columbia

Taxonomic and Nomenclatural Links

Additional Photo Sources

General References