Canada thistle (creeping thistle)
Perennial weed with deep taproot and deep-set, initially perpendicularly-running root stolons that later bend downward geniculately, non-lacteal.
C. arvense likes nitrogen and has a very high phenotypic variability with different subspecies.
Prickly leaves, lilac florets.
Cotyledons: Wide oval, fleshy, dark green, entire, hardly petiolate, prostrate.
Stems: Erect, ramified, spineless, nearly hairless, angularly furrowed, up to 150 cm (59.05 inch) high.
Leaves: First leaves inverse-ovate, following leaves lanceolate, simple to pinnatifid, wavy-ruffled, sessile. Leaf margin with soft to hard spines.