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DescriptionThis adventive perennial plant is 2–3½' tall, branching occasionally in the upper half. The dull green stems are hairless. The alternate leaves are up to 12" long and 3½" across, becoming smaller as they ascend the stems. Most of these leaves are located in the lower half of the plant. They are lanceolate, oblanceolate, or ovate in overall shape, but usually have about 2-5 lobes with pointed tips on each side (pinnatifid). Some of the upper leaves may be unlobed, and occasionally there are plants without significant lobes on the leaves. The margins are dentate-prickly. The upper surface of each leaf is glabrous, while the lower mid-rib is without prickles. At the base of each leaf, there is a pair of small basal lobes that clasp the stem. These basal lobes are usually rather small and well-rounded.