Japanese name: ホソバイヌタデ（細葉犬蓼） Scientific name:Persicaria trigonocarpa
[Overview]
An annual 30–60 cm tall, found on river floodplains.
The stem branches; the lower part creeps along the ground or rises, and the upper part gradually becomes erect.
Leaves are simple and alternate, lanceolate, 3–13 cm long and 0.8–2 cm wide, with pointed tips.
The underside of the leaf has disc-shaped glandular dots that secrete a white resinous substance.
Short hairs grow near the margin on the upper surface of the leaf and on the veins of the underside.
The stipular sheath is tubular, and its marginal hairs are about 2/3 as long as the sheath.
Pseudoracemes from the stem tips and leaf axils bear dense flowers.
The flowers have no corolla, and the pale pink calyx is conspicuous.
The calyx has disc-shaped glandular dots.
The fruit is a 3-ridged achene, glossy and black.
