Canada Thistle (Cirsium arvense L.)

CANADA THISTLE

(Cirsium arvense L.)

 

GROWTH HABIT:  Perennial, erect, up to 4 ft. tall.

LEAVES:  Varies from light to dark green, oblong or lance shaped, deeply cut, spiny toothed margins (some may be smooth); slightly hairy below.  Tremendous leaf variability.

STEMS:  Smooth to slightly hairy, branched at top.

FLOWERS:  Small bristly clusters, ¨ü to ¨ý inch in diameter, light lavender to deep rose purple.  Plants are male or female.

ROOTS:  Extensive, fleshy, creeping rootstocks.

SEEDS:  Smooth, light to dark brown, tipped by a cupped conical point, approx. ¨û¡± long.

OTHER:  Reproduces by seed and creeping rootstocks.