IPM1007, Revised November 2009
A perennial from rhizomes (creeping roots) with conspicuous spines on the leaves and stems. Leaves are arranged alternately along the stem, occur on petioles, and are covered on both surfaces with star-shaped hairs. Leaves also emit a potato odor when crushed, and contain prominent spines on the midvein and petiole underneath. Flowers occur in clusters on prickly stalks and are star-shaped with five white to violet petals and a yellow cone-shaped center. Round berries are produced that are green when immature and turn yellow and wrinkled with maturity. A single berry may contain from 40 to 120 seeds.
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