This variable tetraplod (2n = 44, 48) is a widespread rhizomatous herb in eutrophic woodlands of eastern North America. Generic assignment remains controversial. The species may become known as Persicaria virginiana (L.) Gaertner, as treated by W. Leaves of this species often have a distinct large blackish or purplish distally-pointing V-shaped "chevron", similar to the reddish or blackish marks of some typical Persicaria species, especially in seedlings or prostrate forms: pennsylvanica, lapathifolia, bicornis, maculosa and (more faintly) longiseta. Variation in this character, in leaf pubescence and in rhizome length needs further attaention (W). Closely related East Asian plants have been described as Polygonum filiforme Thunb. and P. neofiliforme Nakai. Some of these plants have even more striking chevrons, with ornamental interest in horticulture (Shaw 2008; W)..