Most species like wet habitats, including roadsides and ditches
Characteristics:
46 species in the genus Polygonum in northeastern North America
Specific species are hard to tell apart, but can be broadly classified into two categories: Smartweeds (in which the flowers are in spike-like terminal clusters) or Knotweeds (in which the flowers are clustered in the leaf axils)
Vary in size by species
Leaves:
Simple leaves
Polygonum are identifiable by a thicker section on the stem at each leaf joint
Leaf base forms a kind of sheath over stem where they join
Flower:
June-November, depending on species
Most are pink or white, although there are some green
Tight terminal clusters of tiny flowers (smartweeds) or smaller clusters nested in leaf axils (knotweeds)