Medicinal shrubs are plants that have been used for centuries to treat a variety of ailments. CASSIA (6 letters) is a genus of flowering plants in the legume family, Fabaceae, and is native to tropical and subtropical regions of the world. SENNA (5 letters) is a large genus of flowering plants in the legume family, Fabaceae, and is also native to tropical and subtropical regions of the world. SUMAC (5 letters) is a genus of flowering plants in the family Anacardiaceae, and is native to temperate and subtropical regions of the world. All three of these medicinal shrubs have been used for centuries to treat a variety of ailments.