Boltonia decurrens (Torr. & A. Gray) Alph. Wood

Boltonia decurrens (Torr. & A. Gray) Alph. Wood. Boltonia decurrens is a rare species of flowering plant in the family Asteraceae known by the common names decurrent false aster and claspingleaf doll's daisy. It is native to the floodplains along the Illinois and Mississippi Rivers in the United States, where the habitat has been drastically altered, leading to its decline. The plant was once distributed across 400 kilometers of riverside forest from LaSalle, Illinois, to St. Louis, Missouri. As the rivers and riparian habitat alongside them have been developed, the plant's distribution has been fragmented into 40 to 43 separate populations. At one point it was thought to have been extirpated from Missouri, but a few populations have been located near St. Louis since the mid-1980s. Despite having declined over time, several populations of the plant contain many thousands of individuals. Populations vary depending on the amount and duration of flooding that occurs in the area each year. The plant is a federally listed threatened species.