Photographer: Merel R. Black
Cirsium arvense (L.) Scop.
Canada thistle, creeping thistle, field thistle
Cirsium: derived from the Greek kirsion, "a kind of thistle;" also cirsos meaning "a swollen vein" for which thistle was once a remedy
arvense: of planted fields
Restricted Invasive - Eradicate!
|Status: ||Introduced - naturalized; ecologically invasive and noxious weed|
|Plant: ||erect, perennial, 1'-4' tall, spiny forb with deep, colony-forming, creeping roots|
|Flower: ||head 1/2" wide with pink disk flowers; inflorescence of many heads in usually flat-topped clusters; blooms June-Oct.|
|Fruit:||dry seed on fluffy, feathery-divided pappus|
|Leaf:||usually pinnately-divided, more or less whitish below|
|Habitat: ||disturbed sites, fields|