Sonchus asper

Common Name: 
spiny sowthistle, spiny-leaved sowthistle
Scientific Name: 
Sonchus asper L. Hill
Family Name: 
Asteraceae (Compositae) - Aster or Sunflower Family
Identification Notes
Life Cycle
introduced annual, reproducing by seed
Stems
upright, smooth, branched sparsely above
Young Plants of Spiny Sowthistle
Young Plants of Spiny Sowthistle
Young Plants of Spiny Sowthistle
Young Plants of Spiny Sowthistle
Young Plants of Spiny Sowthistle
Leaves
alternate, lobes pinnate or entire above, margins spiny and wavy, white mid-vein, large round basal lobes clasping - curled downward, often dark green and glossy
Leaves of Spiny Sowthistle
Leaves of Spiny Sowthistle
Leaves of Spiny Sowthistle
Flowers
heads of yellow ray (ligulate) florets; terminal clusters; form "puffball" when mature
Flower Heads of Spiny Sowthistle
Flower Heads of Spiny Sowthistle
Other: 
contains milky sap