Polygonum ciliinode (synonym Fallopia ciliinodis[1]) is a species of flowering plant in the family Polygonaceae, native to central and eastern Canada, and the north-central and eastern United States.

[3] Article 60 of the International Code of Nomenclature for algae, fungi, and plants requires the correction of improperly formed "compounding forms",[4] and the International Plant Names Index has corrected it to "ciliinode".

[2] Polygonum ciliinode is part of the tribe Polygoneae of the subfamily Polygonoideae.

[5] However, like many species in the family Polygonaceae, it has been placed in different genera within this group, including in Fallopia and Reynoutria.

[2] A 2015 molecular phylogenetic study (in which the species was treated as Fallopia cilinodis) found that it was weakly supported as a sister to the "DAP clade" (see the following cladogram), although plastid data alone placed it in the "RMF clade".