Northern IWM factsheet – common sowthistle
September 24, 2018
Common sowthistle (Sonchus oleraceus L.), also known as milk thistle, is a dicotyledonous annual weed. The plants are erect and fleshy and possess hollow, smooth stems that exude a milky latex when damaged. The weed can grow up to 1.5 m in height. Plants of common sowthistle can be either present as a rosette or upright in their growth form. Its leaves may vary in colour and the amount of serration on their margins (Figure 1). Common sowthistle seeds possess a pappus, which helps in seed dispersal through the wind.