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Related to Amorpha: lead plant
false indigo, a genus of shrubs and semishrubs of the family Leguminosae. Its leaves are odd-pinnate and compound; its flowers are in clusters or panicles, small, and mostly violet, purple, or white with a corolla in which only the large superior (posterior) petal flag is developed while the other petals are reduced. There are about 20 species in North America. Many of them are cultivated in the botanical gardens of the USSR. Amorpha fruticosa, a shrub not over 4 m tall with purple-blue leaves 7 to 15 cm long arranged in panicles, is grown as an ornamental.