Eleocharis tuberosa.

Botanical name: 

Eleocharis tuberosa Schult. Cyperaceae. Water-Chestnut.

East Indies. This plant is grown in southern China for its roots, for which there is a great demand in all Chinese towns." Royle says it is the pi-tsi of the Chinese and that the round, turnip-shaped tubers are eaten. Loudon calls it the water-chestnut and says it is grown in tanks by the Chinese for the tubers. Ainslie says the root is in high estimation either for the pot or as a medicine. This rush can be subjected to regular cultivation in ponds, says Mueller, for the sake of its edible, wholesome tubers. It is largely cultivated all over China. The tuber is sweet and juicy with a chestnut flavor and is universally used as food. A kind of arrowroot is made from it.

Sturtevant's Edible Plants of the World, 1919, was edited by U. P. Hedrick.