Dioscorea bulbifera f. domestica(air potato, "Kashuimo")
Japanese name: カシュウイモ（何首烏芋） Scientific name:Dioscorea bulbifera f. domestica
[Overview]
A climbing perennial.
It has a large, flattened-spherical tuberous root with a black outer skin.
The leaves are simple and alternate, heart-shaped to round, 5–13 cm in both length and width, abruptly pointed at the tip, and hairless on both surfaces.
The leaf margin is entire.
The petiole is 3–9.5 cm long, and large bulbils form in the leaf axils, some weighing as much as 1 kg.
It is dioecious.
Both male and female inflorescences hang down.
Both male and female flowers are purplish yellow-green, with 6 lanceolate tepals that do not open flat.
In Japan only female plants are said to exist, and fruiting is rare.
The fruit is an oblong capsule 1.5–2.5 cm long and 1–1.5 cm wide, with 3 wings.
[History]
A cultivated plant native to China.
[Uses]
The tuberous root is used medicinally.
The bulbils have little bitterness and are eaten.
[Cultivation]
Propagate by bulbils.
It is easy to grow in a sunny, well-drained place.
