Tong oil from Langzhong

Tong oil from Langzhong

　　The mountainous areas in central and northeastern Sichuan feature high elevation, good drainage, moderately acidic or alkaline soil, long hours of sunlight in summer, and brief cold spells in winter — all ideal conditions for tung tree growth. Moreover, tung trees grow quickly, yield returns early, and are resistant to aging. As a result, tung trees can be found “on every hill and in every household” across rural Langzhong. In the bright spring month of March, tung blossoms burst into bloom, covering the hills and ridges like gorgeous brocade. A local saying goes: “Hey young lad, don’t be too cheerful (gu — meaning happy), the tung blossoms may freeze in March”; “Plant mulberry and tung trees, and your family will never be poor.”

　　According to the 1945 “Overview of Minzhong County”: “The tung oil produced in Langzhong is of the highest quality, with a concentration as high as 27 degrees, crystal clear transparency, strong adhesion, and resistance to extreme temperatures, acids, alkalis, corrosion, and rust. In the past, it was mostly used for lighting by local households, with any surplus sold in markets. The Chongqing Tung Oil Company set up purchasing stations and exported it to Europe and America, where it gained considerable renown in the international market.”

　　Tung oil is a type of vegetable drying oil and an important material for medicine and wartime supplies. In 1976, Langzhong was designated as a tung oil production base county of Sichuan Province. By 1980, tung seed production reached 3.856 million kilograms, earning recognition and rewards from both the Ministry of Commerce and the Ministry of Foreign Trade. In 1985, the tung seed yield hit 4.75 million kilograms. Among tung oils, Donghe tung oil is the most famous; as early as 1516, it was exported to Southeast Asia, Europe, and America, enjoying a high reputation.