Cassava

Manihot utilissima or M. esculenta; ubi kayu (in Java, ketéla or singkong). This unexciting but valuable tuber was brought to Asia from South America. It will flourish in very dry conditions. It consists mostly of starch, but also contains a form of prussic acid, and the flesh is therefore grated, washed, pressed and finally baked to make it safe. Further processing produces tapioca. However, ordinary boiling makes cassava completely safe. Cassava leaves are also used in cooking.