Saururus cernuus

Saururus cernuus (lizard's tail, water-dragon, dragon's tail, swamp root) is a species of herbaceous perennial plant. The plant grows up to about 1 metre (3+1?2 ft) tall. The leaves are somewhat heart-shaped and are arranged alternately on the stem. The inflorescence is 7+1?2 C20+1?2 centimetres (3 C8 in) long. After maturing, the white flowers turn brown, giving the plant its name, lizard's tail. The plant can be found in the wetlands of eastern North America. It is an important food source for animals such as beavers, which notably reduce its abundance. Some Native Americans used the plant medicinally, using it to soothe inflammation, fevers, and body aches.

from Wikipedia