arrow-leaved tearthumb (Persicaria sagittata)

Persicaria sagittata, common names American tearthumb, arrowleaf tearthumb, or arrowvine, is a plant species widespread in the eastern half of North America as well as in eastern Asia. It has been found in every state and province from Texas to Manitoba to Newfoundland to Florida, plus Colorado and Oregon. It also grows in China, the Russian Far East, Siberia, Korea, Japan, northern India and Mongolia. It grows in moist areas along lake shores, stream banks, etc.