Japan Flora: Small tree with gla­brous dark brown to dark purple-brown or sometimes slightly grayish branches; leaves obovate-cuneate to broadly obovate or obovate-orbicular, 6-10 cm. long, 4-9 cm. wide, rounded, truncate or emarginate, cuneate at base, glabrous above, often slightly pilose on nerves, with spreading hairs near axils be­neath, serrulate, the lateral nerves of 7 to 9 pairs, slightly raised and rather reddish beneath, the petioles 8-15 mm. long; staminate inflorescence terminal, consisting of 4 or 5 aments, the pistillate from the upper axils, consisting of 1-4 aments; fruiting aments ovoid-ellipsoid, 15-20 mm. long, 8-12 mm. in diameter.--- Mar.-Apr. Along rivers

Honshu (Tokaido, Kinki, and Chugoku Distr.), Shikoku.