Persicaria punctata (Elliott) Small
Family: Polygonaceae
dotted smartweed
[Persicaria punctata var. eciliata (Elliott) Small,  more]
Persicaria punctata image
Kenneth J. Sytsma  
Etymology: Persicaria: peach-like, the medieval name for knotweed
Plants: erect or sprawling, perennial/annual, up to 40" tall, aquatic to terrestrial forb
Leaves: alternate, narrowly lance-like, smooth, usually up to 8" long by 3/4" wide
Flowers: white to greenish, 5-parted, petals and petal-like sepals united at the base; inflorescence thin, interrupted, spike-like, up to 4” long clusters either erect or arching on a stalk jointed at the top; blooms July-Sept.
Fruits: brown/black, smooth, shiny, dry seed
Habitat: sun; wet; swamps, shallows