AppearanceAchyranthes japonica is a perennial herb that can grow up to about 6.5 ft. (2 m) tall. Stems are glabrous or slightly pubescent.FoliageOvate-elliptic leaves are opposite and simple. Margins are entire and repand (slightly wavy). The base of the leaf is tapering and the apex is acute to acuminate.FlowersThe small flowers have no petals and are clustered tightly on the inflorescence which occur at the ends of the stems and upper branches. They flower in summer.FruitThe fruits are elliptic utricles that are held tightly along the stem. Fruits contain a single seed and each plant produces many seeds. Each fruit has a pair of stiff bracts that can attach to fur or clothing, allowing the seed to be easily spread.Ecological ThreatAlthough Achyranthes japonica prefers partial sun and moist soils it can survive in shade and dry conditions. It readily invades bottomland forests, wooded riverbanks, roadsides, ditches and field edges. Achyranthes japonica can form dense monocultures shading and outcompeting native plant species.