(David Hershey) meinte:

The USDA Plants Database lists it as occurring in all but 9 of the
continental states. It uses the name Polygonum cuspidatum.

http://plants.usda.gov/


Here's the list of synonyms from this site:

Polygonum cuspidatum Sieb. & Zucc.
Fallopia japonica (Houtt.) Dcne.
Pleuropterus cuspidatus (Sieb. & Zucc.) Moldenke
Pleuropterus zuccarinii (Small) Small
Polygonum cuspidatum Sieb. & Zucc. var. compactum (Hook f.) Bailey
Polygonum zuccarinii Small
Reynoutria japonica Houtt.

Simple and clear thing, a scientific name, isn't it?