This perennial is a member of the dogbane family. It grows up to 5 feet tall. It is present in a moist area of the wetlands, although it is more commonly found in roadsides and the edges of woods. Its lanceolate leaves are 2 to 5 inches long, alternate, and considerably narrower than those of other dogbanes. The small, cup-shaped, white flowers form a loosely organized cluster in July. It has a milky sap.

This plant is poisonous, although Native Americans used it to make tea for heart ailments and as a diuretic. The stems can be used to make rope, hence its name.