Persicaria perfoliata (basionym Polygonum perfoliatum[1]) is a species of flowering plant in the buckwheat family.

[7] This implies that this species cannot be imported, cultivated, transported, commercialized, planted, or intentionally released into the environment in the whole of the European Union.

[8] Persicaria perfoliata has a reddish stem that is armed with downward pointing hooks or barbs which are also present on the underside of the leaf blades.

The light green leaves are shaped like an equilateral (equal-sided) triangle and alternate along the narrow, delicate stems.

However, the introduction of P. perfoliata somewhere between the late 1930s and 1946 to a nursery site in Stewartstown, York County,[10] Pennsylvania, produced a population of this plant that did become established in the wild.

[11] Persicaria perfoliata is primarily a self-pollinating plant (supported by its inconspicuous, closed flowers with little scent), with occasional outcrossing.

This activity is probably encouraged by the presence of a tiny white food body (elaiosome) on the tip of the seed that may be attractive to the ants.

Its fruits can remain buoyant for 7–9 days, an important advantage for dispersing seed long distances in stream and river environments.

The long vines frequently hang over waterways, allowing fruits that detach to be carried away in the water current.