Previous to transplanting, the land is well prepared by deep plowing and thorough harrowing, and rows are laid off 15 feet apart. The young trees are set in these rows 4 feet apart, either by hand or with a tree-setting machine. This machine is simply a tobacco-setting machine fitted with a trench opener set to open a furrow 8 inches deep, in which the trees are placed. The trees used for transplanting are headed back to within 1 inch of the crown, and the lower end of the taproot and all large laterals are removed. The taproot of the tree as planted is thus reduced in length to 8 or 10 inches and varies in diameter according to the vitality and previous growth of the seedling. Transplanting should be done in the winter months, when the trees are dormant. Cultivation is begun as soon as the trees put forth shoots in the spring and continued until the rainy season of each year. After the rainy season the plants are again cultivated and all grass and weeds removed. At times cultivation is necessary during the rainy season in order to keep the trees from becoming smothered and killed by the fast-growing weeds. One-horse cultivators drawn by mules or a gang cultivator drawn by a light tractor may be used. In three or four years, after transplanting, the trees should be from 7 to 8 feet high. They are then trimmed by means of a special machine[3] to form an =A=-shaped hedge and the trimmings distilled for the oil and camphor gum. Trimming is carried on when the trees are in the dormant stage, which is twice each year, usually November to January and May to June. The summer dormant season is somewhat irregular and governed entirely by local conditions. [3] A detailed description of this machine is given in U. S. Dept. of Agr. Cir. 78, entitled "A Machine for Trimming Camphor Trees." 1920. The cuttings are hauled from the field to the distilling plant, and if many large branches are present they are run through a heavy ensilage cutter. For distillation they are packed in large iron retorts, to which steam is admitted at the bottom. The outlet pipe of the retort is connected with a specially constructed condensing apparatus in which the oil and camphor carried over by the steam are condensed and partly collected. Portions of oil and camphor not collected in the condenser are caught in a tub fitted with an outlet siphon which carries away the excess condensed steam but leaves the oil and camphor behind. When removed from the condenser the product is very crude, consisting of a mixture of oil, water, and camphor. This mixture is either thrown into a centrifuge and the oil and water removed or it is placed in large cylindrical vats and the oil and water allowed to drain out. The oil is then separated from the water by means of a siphon. The camphor and oil are marketed separately.