Japanese Knotweed near Swamp Creek

Reynoutria japonica (wikipedia.org) Reynoutria japonica, synonyms Fallopia japonica and Polygonum cuspidatum, is a species of herbaceous perennial plant in the knotweed and buckwheat family Polygonaceae. Common names include Japanese knotweed and Asian knotweed. It is native to East Asia in Japan, China and Korea. In North America and Europe, the species has successfully established itself in numerous habitats, and is classified as a pest and invasive species in several countries.
Swamp Creek (Washington) (Wikipedia) Swamp Creek is a tributary of the Sammamish River in Snohomish and King counties, in the U.S. state of Washington. It is also known as dxʷɬ(ə)q̓ab in Lushootseed, meaning “a wide place”.

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