|Polygonum debile, an
annual of the height of 10-50cm with some retrorse hairs on nodes,
grow in colonies in forests in mountainous regions. Leaves are of
alternate phyllotaxis; lower leaves have long pedicles, but upper
ones do not. The leaf blades are triangular with the length of 2-5cm
and entire, and also with a V-shaped blackish stache on each
surface. A few small petal-less white flowers come on each bi-forked
peduncle emerged from leaf axils; sepals are cleft in five lobes.
Bloom time: August-September.