water spinach, kangkong, swamp morning-glory
cosmopolitan; warm regions of world
Ipomoea aquatica Forssk.
U.S. Federal Noxious Weed: Ipomoea aquatica
Identification: No single diagnostic feature distinguishes Ipomoea aquatica. Rather, a combination of features may help to distinguish it from other, particularly aquatic, species in the genus: With milky sap. Stems hollow, floating when in water, to 3 m long and can be much longer, rooted at nodes. Petioles 3-14 cm long. Leaf blades held erect above water when stems floating, variable in shape, usually narrowly triangular, sagittate or hastate, 4-17 cm long, apex pointed; leaf base truncate to broadly sagittate or hastate, basal lobes triangular, lobe apices acute or obtuse, tips acuminate. Pedicels and peduncles 2-7 cm long. Sepal lobes subequal, +/- 6 mm long. Capsule diameter +/- 8-10 mm.
Ipomoea aquatica is a serious weed in numerous crops in over 60 countries around the world and is an aquatic weed on the U.S. federal noxious weed list. Ipomoea fistulosa is also a serious weed in irrigation canals.
Perennial. Stem creeping, rooting at each node, thick and spongy when floating. Leaves widely spaced, alternate; petiole elongate; leaf blade cordate or sagittate to linear or triangular; margin entire. Inflorescence axillary, of one to a few flowers in a cyme. Sepals 5, green; corolla tubular, large, funnel-shaped, lobes 5, color variable, usually white to purple. Fruit a capsule. Dispersal by stem fragments and seeds.
terrestrial or aquatic, floating or wet ground
In this genus consisting of nearly 500 species worldwide, only two species can be considered aquatic. Ipomoea is commonly cultivated for consumption.