Spiny Sowthistle
Sonchus asper

Spiny sowthistle is a winter annual weed that forms from a basal rosette. Leaves are deeply lobed, clasp the stem, and have spiny margins. Stems are often green-to-purple in color. Leaves and stems exude a "milky" white sap when broken. Yellow flowers are present in mid-to-late spring in clusters at the top of the plant. Annual sowthistle (Sonchus oleraceus) is similar in appearance except that the uppermost leaves lack a petiole.
Main Plant Image

DetailsChemical ControlWeed List

Spiny Sowthistle
Sonchus asper

Chemicals exhibiting activity against this weed

Always refer to the product label for specific information on proper product use, tank-mix compatibility, and turfgrass tolerance. Products containing more than one of the chemicals listed below may offer improved control. Read Full Disclaimer

SeasonEmergenceChemical
CoolPreRegular mowing; isoxaben, oxadiazon
Post2,4-D, carfentrazone, dicamba, MCPP, MCPA, sulfentrazone, triclopyr, triclopyr + clopyralid
WarmPreRegular mowing; isoxaben, oxadiazon
Post2,4-D, atrazine, carfentrazone, dicamba, imazaquin, MCPP, MCPA, metsulfuron, simazine, sulfentrazone, triclopyr, triclopyr + clopyralid
DetailsWeed OverviewWeed List

Spiny Sowthistle
Sonchus asper

Life cycle:Winter annual
Growth Habit:Basal rosette (upright)
Leaf Type:Elliptical
Leaf Margin:Lobed with spines
Leaf Hairs:None
Leaf Venation:Pinnate
Leaf Arrangement:Alternate
Root Type:Taproot
Flower Color:Yellow
Chemical ControlWeed OverviewWeed List