It has been known to the Chinese from the earliest times, and has been always named by them the Huai tree. In the Chou Li, a Chinese classical book, dating from several centuries before the Christian era, it is mentioned as having a place in official audiences. In front of the high officials were placed three Sophora trees, beside which stood the counsellors. It was also used as firewood, and was planted in cemeteries, being the tree prescribed by law to be planted beside the tumulus, 4 feet high, in which officials of low degree were buried. The tumulus of the emperor was 30 feet high, and around it pine trees were planted. Feudal princes were honoured with cypresses; and common people were only permitted to have willows around their tombs. The Sophora was also used medicinally from the earliest times in China, the flowers, fruit, bark, and root being all employed. In the Erh-ya, the oldest Chinese dictionary (twelfth century b.c.), the Huai tree is called the guardian of the palace; and it is said to open its leaves by night and close them by day. The text is probably corrupt, and the periods of expanding and folding of the leaves are reversed. This is perhaps the first reference in any literature to the phenomenon of the sleep of plants. The term guardian of the palace no doubt refers to its use in official audiences.
With regard to the uses of Sophora in China at the present day, in addition to its ornamental character as a tree planted frequently in the courtyards of temples, it is also of considerable economic importance. In commerce the flower-buds (Huai-mi, huai-hua, huai-tze), and pods (huai-chio, huai-shih) are met with everywhere; but considerable confusion has arisen in books as to the exact uses of these products. Shirasawa (l.c.) is inaccurate in stating that the Chinese use the bark to dye paper and cloth of a yellow colour. Mouillefert[1] says the leaves are used for dyeing; but this is also an error. The facts are simple: the flower-buds are used as a dye, and the pods as a medicine.
The flower-buds, as seen for sale, are mixed with stalks, etc., and are evidently collected when quite young as they are only about ⅛ to ¼ inch long. They are oval and pointed at the stalked end, dark greyish in colour, and tasteless. When immersed in water they impart to it a fine yellow colour. These flower-buds, packed in large sacks, are exported in considerable quantity from Shanghai and Tientsin. Consul Meadows in a letter to Kew gives an account of the process of dyeing, which is one for dyeing blue cloth a green colour rather than for obtaining a yellow colour.[2] Debeaux[3] asserts that the buds are moistened with water, and a quantity of common salt is added; the mixture is then put in a press, which squeezes out a liquor with which cotton or silk may be dyed yellow. He adds that the leaves do not contain any yellow colouring matter.
Every part of the tree abounds in a purgative principle; and it has been asserted that it is dangerous to work with the wood when it is fresh, owing to the
- ↑ Mouillefert, Traité des Arbres, 629.
- ↑ The process, according to Meadows, is as follows:—"To dye a piece of cotton cloth of narrow width (1½ feet) a thousand feet long, a mixture is made of 42 lbs. of Sophora buds, 8 lbs. of alum, and 666 lbs. of water, which is boiled in a large pot for six hours. In Chekiang both cottons and silks are first dyed a light blue, and are then put in the mixture just described, and all is boiled over again for three or four hours; the cloth is then taken out and dried in the sun. It is afterwards boiled and sun-dried once or twice again, according as a lighter or darker tint of green is required."
- ↑ Debeaux, Note sur quelques matières tinctoriales des chinois (1866).