Cinchona ledgeriana" had a yield of 8 to 13 percent quinine in bark grown in Dutch Indonesia which effectively out-competed the British Indian production. It was only later that the English saw the value and sought to obtain the seeds of "C. ledgeriana" from the Dutch. During World War II, the Japanese conquered Java and the United States lost access to the cinchona plantations that supplied war-critical quinine medication. Botanical expeditions – called Cinchona Missions – were launched in 1942-1944 to explore promising areas of South America in an effort to locate cinchona species that contained quinine and could be harvested
Cinchona "plea for the correct spelling of the genus "Chinchona"". A Spanish physician, Juan Fragoso wrote of bark powder from an unknown tree in 1600 that was used for treating various ills. Nicolas Monardes also wrote of a New World bark powder used in Spain in 1574. Both identify the sources as trees that do not bear fruit and having heart-shaped leaves and it has been suggested that these references could be to "Cinchona" species. The name Quina-Quina or Quinquina was suggested as an old name for Cinchona used in Europe and based on the native name used by the Quechua