Tung oil comes from the seeds of Aleurites fordii, a deciduous shade tree native to China. It belongs to the Euphorbia Family (Euphorbiaceae) along with the candlenut tree , another species with seeds rich in unsaturated oils. For centuries tung oil has been used for paints and waterproof coatings, and as a component of caulk and mortar. It is an ingredient in "India ink" and is commonly used for a lustrous finish on wood. In fact, the "teak oil" sold for fine furniture is usually refined tung oil. Some woodworkers consider tung oil to be one of the best natural finishes for wood. Light: Nearly full sun is necessary for good growth. Moisture: Tung can take drought, but it does much better in reliably moist soil. Soak seeds in water for 5-7 days, then plant them where they are to grow in late spring. Alternatively, seeds may be sown in a warm greenhouse in the very early spring to produce transplants to be set out late the following spring. Germination takes at least two months. If the trees are started outdoors, a summer side-dressing of 5-10-5 with zinc sulfate is recommended.