IPM1007, Revised November 2009
A taprooted biennial that may reach as much as 10 feet in height. Primarily a weed of pastures and roadsides throughout the United States, but becoming more problematic in no-till cropping systems. Leaves are alternate, triangular in outline, 8 to16 inches long, finely divided, and often have a dark glossy green appearance. Stems that are produced during the second year of growth are erect, branching, without hairs, ridged, hollow except at the nodes, and distinctly purple-spotted. Large white, flat-topped flowers (compound umbels) occur at the ends of the branches.
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