Common Name: Canada thistle, creeping thistleScientific Name: Cirsium arvense (L.) Scop syn. Carduus arvensisFamily Name: Asteraceae (Compositae) - Aster or Sunflower FamilyIdentification NotesLife Cycleintroduced perennial, reproducing by seed and creeping roots Stemsupright, tall, branched above, ridged Leavesalternate, oblong to lance-shaped, sessile, crinkly margins, lobes irregular and spiny Flowers heads of rose-purple (sometimes white) disk (tubulate) florets; spineless bracts; terminal and axillary above; dioecious