-Plants (Kingdom Plantae)

-Vascular Plants (Phylum Tracheophyta)

-Flowering Plants (Subphylum Angiospermae)

-Dicots (Class Magnoliopsida)

-Pinks, Cactuses, and Allies (Order Caryophyllales)

-Knotweed Family (Family Polygonaceae)

-Subfamily Polygonoideae

-Tribe Persicarieae

-Subtribe Persicariinae

-Knotweeds, Smartweeds, and Waterpeppers (Genus Persicaria)

-Swamp Smartweed (Persicaria hydropiperoides)

Grows in moist to swampy areas, often growing in mud. All parts of this plant have an acrid pepper-like flavour, and the plant has a long history of use in traditional medicine.