Common name: Spiny Sowthistle
Latin name: Sonchus asper L.
Life Cycle: Annual
Description: Winter annual weed that is much more prickly to the touch than Annual sow-thistle (S. oleraceus). Stem leaves have clasping auricles and spiny-toothed leaf margins. Like other sow-thistles, it exudes a milky sap from the stem when cut. This can be used to distinguish it from thistles like Canada Thistle, Horrible Thistle, and others, which do not exude a mikly sap when cut.
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