About Cirsium hookerianum Nutt.
Cirsium hookerianum, commonly called Hooker's thistle or white thistle, is a North American thistle species native to western Canada and the northwestern United States. Its range covers the northern Rocky Mountains, plus parts of the northern Cascades and Coast Ranges, occurring in the Canadian provinces of Alberta and British Columbia, and the U.S. states of Washington, Idaho, Montana, and Wyoming.
This species is a biennial or perennial herb that can reach up to 150 cm (60 inches) in height, and it grows a large taproot. Its upper leaf surface is green, while the underside is usually white and woolly, with spines along the leaf edges. Plants typically produce several flower heads, which contain white or pink disc florets and have no ray florets. Cirsium hookerianum grows in mountainous habitats, specifically in grasslands, meadows, and along forest edges.
