Polygonum is a genus of annual or perennial vines and herbs (ours). Stipules consist of a membranous sheath below each leaf (ocreae), the upper margins often bristly. Stems vining.
Leaves usually alternate, simple (1-parted), margins smooth (entire).
Flowers small, petals and sepals alike (tepals). Ovary attached above tepals (superior).
Fruit consists of developed seed (achene), flat or 3-sided usually held within old tepals.