Fallopia scandens
Fallopia scandens, the climbing false buckwheat, is a species of Fallopia native to North America. It is a herbaceous perennial plant which grows from to 1–5 m (3–16 ft) tall. Although they are semi-erect during bloom, when they are producing fruit, they hang from their pedicels in a downward position. Both the fruit and flower are greenish-white in appearance. In North America, it is often misidentified with Fallopia dumetorum, a species endemic to Europe.
References
Media related to Fallopia scandens at Wikimedia Commons