Persicaria thunbergii, an
annual herb height of 0.3-1m, grows in colonies in damp-to-wet
spaces, such as water's edges, paths between rice fields, etc. The
stems have downward prickles and lower parts creep on the ground.
Leaves are alternate, ovate to hastate, 4-10cm long, tips pointed,
and bases spread like ear shape. Flowers from red-purple to white
bloom in mass on branch tops. Bloom time: July-October.