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Photographer: Merel R. Black
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Family Asteraceae
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!
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| 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 |
| (Glossary) |
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 Scop.&phog=Botanical Illustration&spcode=CIRARV)
 Scop.&phog=Botanical Illustration&spcode=CIRARV)
 Scop.&phog=Botanical Illustration&spcode=CIRARV)
 Scop.&phog=Kurt Stüber&spcode=CIRARV)
 Scop.&phog=Matthew L. Wagner&spcode=CIRARV)
 Scop.&phog=Christopher Noll&spcode=CIRARV)
 Scop.&phog=Paul Drobot&spcode=CIRARV)
 Scop.&phog=Paul Drobot&spcode=CIRARV)
 Scop.&phog=Paul Drobot&spcode=CIRARV)
 Scop.&phog=Robert Bierman&spcode=CIRARV)
 Scop.&phog=Stephen L. Solheim&spcode=CIRARV)
 Scop.&phog=Stephen L. Solheim&spcode=CIRARV)
