Distribution: Occurring west of the Cascades crest in Washington, where known only from Clallam County; Washington to California and Idaho, also in central and eastern U.S.
Habitat: Disturbed, open areas at low elevation.
Origin: Introduced from Europe
Conservation Status: Not of concern
Pollination: Bees, flies, beetles, wasps
[none provided]
Publication: Sp. Pl. Ed. 2,. 2: 1151. 1753.
PNW Herbaria: Specimen records of Carduus pycnocephalus ssp. pycnocephalus in the Consortium of Pacific Northwest Herbaria database.
WA Flora Checklist: Carduus pycnocephalus ssp. pycnocephalus checklist entry.
OregonFlora: Carduus pycnocephalus ssp. pycnocephalus information.
E-Flora BC: Carduus pycnocephalus ssp. pycnocephalus atlas page.
CalPhotos: Carduus pycnocephalus ssp. pycnocephalus photos.
USDA Plants: Carduus pycnocephalus ssp. pycnocephalus information.
