*Panicum bisulcatum Thunb.

Aquatic or semi-aquatic glabrous perennial with branching stems floating on water or rooting at the nodes in mud. Spikelets lanceolate-elliptic, acute, 2.5–3 mm long. Panicle loose; the flowering culms and panicle 20–80 cm high. Leaf blades 2–15 cm long, 4–13 mm wide. Grows along streams. Introd. from Asia. Fl. summer. Black-seeded Panic