IPM1007, Revised November 2009
Summer annual broadleaf
An annual or biennial weed of nurseries, orchards, roadsides and agronomic crops. Leaves are arranged alternately along the stem of mature plants and range from 2 to 14 inches in length. Most leaves are distinctly lobed and have leaf bases that clasp the stem. All leaves have prickles that occur along the leaf margins and along the midvein on the lower leaf surfaces. Leaves emit a milky sap when cut and become progressively smaller up the flowering stem. Stems are erect, hollow and branching in the upper portions of the plant. Many small yellow flowers with 5 to 12 toothed petals are produced in the upper portions of the plant.
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