Marshpepper smartweed, arsmart, biting knotweed, biting parsicaria, biting tongue, common smartweed, doorweed, lakeweed, pepperplant, red knees, red shanks, red sharks, sickleweed, smartweed, water pepper, water smartweed.
An annual that grows to 1 to 2 feet in height. It is erect and branched at base. Stems are reddish; and leaves are narrowly lanceolate and alternate, with smooth margins 1 to 4 inches long. Produces numerous small greenish flowers that are formed close together on the ends of nodding terminal spikes.
July to October.
The herb is a diuretic and has been used in certain uterine disorders. In Europe it is used as a hemostatic drug to control internal and hemorrhoidal bleeding.