any of about 40 species of herbaceous plants constituting the genus Eupatorium of the composite family Asteraceae, native primarily to tropical America. The North American plant known as boneset is E. perfoliatum, also known as agueweed and Indian sage. It is common in wet places and is a coarse, rough, hairy perennial about 0.6 to 1.8 metres (2 to 6 feet) high. Its lance-shaped, toothed, and wrinkled leaves are joined together at their bases around the stem. In August the plants bear small, tubular, white flowers in numerous heads that form a flat and branched cluster
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