Canada Thistle | South Dakota Department of Agriculture

Canada Thistle

Roots: Spreading, pieces capable of producing plants, extensive.

Stems: Erect, hollow, branched above, ridged.

Leaves: Dark green, wavy and very spiny

Seed: The tuft of hairs attached to the top of the seed allows the seed to be carried by wind, small, long lived.

Flowers: Small, up to 3/4 inch diameter, pink to purple, occasionally white, male and female flowers on different plants.

Origin: Eurasia and North Africa, brought into Canada as a crop seed contaminant.

Poisoning: May accumulate high nitrate levels.