Ukon no Tachibana (the mandarin orange tree of Ukon) is a mandarin orange tree which existed on the right of the South floor down from the Shishin-den Hall (hall for state ceremonies) of the Imperial Palace in the Heian-kyo.
右近橘（うこんのたちばな）は、平安京内裏紫宸殿からおりる南階の、紫宸殿から見て右にあったタチバナの樹。