Sonchus oleraceus L.
Sow Thistle is a winter annual that is found in various soil types of the South Texas Plains and the Edwards Plateau. It reaches 6 to 24 inches in height and has spiny lobed leaves. The flower head is made of numerous yellow ray flowers and no disk flowers and is 5/8 to 1 inch in diameter. Sow thistle is considered a weed in most yards and usually blooms all year. The milky sap of this plant was once used for eye ailments and skin imperfections. The leaves are eaten by white-tailed deer.
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