Alisma canaliculatum A.Braun & C.D.Bouché

Tubers 1-3 cm in diam. Aerial leaves with petiole 9-30 cm; leaf blade slightly falcate, lanceolate, 6-45 × 1-5 cm, 3-5-veined, base cuneate or gradually attenuate to petiole, apex acuminate. Panicles 35-65 cm, in 3-6 whorls of 3-9 branches. Pedicel 2-4.5 cm. Sepals oblong, 3-3.5 mm. Petals white, suborbicular, margin irregular. Anthers ca. 0.8 mm. Carpels regularly arranged; styles recurved, ca. 0.5 mm, stigmatose in upper ca. 1/3 of their length. Achenes obovoid, 2-2.5 mm, 1-canaliculate on back; lateral pericarp opaque, thickish. Fl. and fr. May-Oct. 2n = 28, 34, 40, 42*.

It is a temperate plant. It grows on the edges of lakes and streams. It grows naturally in wet places all over Japan. It suits wet ground and water up to 25 cm deep.

CAUTION; This plant probably contains poisons which are destroyed on cooking or drying. The young leaves are reported cooked and used in soups.

Plants can be grown from seed or by division of the plant. Fresh seed should be used and pots should be kept in water to keep the soil wet.