Canada thistle (Cirsium arvense)
Shot in Edmonton Alberta
Canada thistle is a creeping perennial that reproduces from vegetative buds in its root system and from seed. An aggressive, creeping perennial weed that infests crops, pastures, range-land, roadsides and non-crop areas. Generally, infestations start on disturbed ground, including ditch banks, overgrazed pastures, tilled fields or abandoned sites.