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DescriptionThis introduced perennial plant is 2-4' tall, branching occasionally. The stems are glabrous or sparingly hairy. The alternate leaves are up to 12" long and 4" across, and more or less ovate in outline. They are double or triple pinnately lobed, which provides them with a fern-like appearance. In var. crispum, as revealed in the photograph below, the margins of these lobes are curled, whereas in the typical variety these margins are flat. The smallest lobes are dentate along the margins. The leaves have flat petioles and they are largely hairless.