Dog mustard

Erucastrum gallicum

Annual or winter annual, spreading by seeds; autogamous; stems 6 inches to 2 feet (15 cm. to 6 dm.) high; flowers pale yellow; throughout our area, but reaches its greatest abundance in the mid-west; cultivated fields, roadsides, railway beds, and waste places; introduced from Europe and Asia. It was first seen in 1903, in the United States.