Woo Jang-choon (April 8, 1898 – August 10, 1959) was a Korean-Japanese agricultural scientist and botanist, famous for his discoveries in the genetics and breeding of plants.[
Woo was born and raised in Japan, overcoming poverty and discrimination in Imperial Japan to become a prominent researcher and teacher. When Korea was freed of Japanese rule in 1945, Woo left his family in Japan and traveled to Korea to lead the country's efforts in botany and agriculture. There is a memorial museum in the port city of Busan where he lived and worked in Korea, honoring his life and accomplishments.
Woo is credited in scientific literature as Nagaharu U, a Japanese reading of the Chinese characters of his Korean name (the pronunciation of his family name 禹 can be Romanised as U in both Japanese (う) and Korean (우)).
Woo was born on April 8, 1898, in either Akasaka, Tokyo or Hiroshima and raised in Kure, Hiroshima, he was the first son of a Japanese mother, Sakai Naka (酒井 仲) and Korean father, Woo Beom-seon (禹範善, 우범선). Woo Beom-seon served as the commander of the first battalion of the Hullyeondae (a Japanese-trained Korean military force) during the late period of the Joseon dynasty and had sought political asylum in Japan. He was involved in the Gaehwapa movement (a modernization faction) and was suspected of involvement in the Eulmi Incident, the assassination of Queen Min and the murder of two other women in 1895. 56 Japanese nationals were arrested and tried on suspicion of involvement, but acquitted in a Japanese court due to lack of evidence. Meanwhile, Queen Min's son, Prince Sunjong, accused Woo Beom-seon of complicity in the murders and Woo Beom-seon fled to Japan.