silphium trifoliatum

Silphium trifoliatum, commonly known as whorled rosinweed, is a species of flowering plant in the aster family (Asteraceae). It is native to the eastern United States, where it is found east of the Mississippi River. Its natural habitat is open, grassy areas such as prairies, river cobble bars, and roadsides. It is a tall perennial that produces heads of yellow flowers in mid-summer through fall.This species is considered to be a variety of Silphium asteriscus by some authors. It can be distinguished ...