1419

3: Dye and tannin-producing plants

Sophora japonica L.

Mant. Pl. 1: 68 (1767).

LEGUMINOSAE

2n = 28

Styphnolobium japonicum (L.) Schott (1830).

Japanese pagoda tree, umbrella tree, Chinese scholar tree (En). Indonesia: sari kuning, sari cina. Vietnam: hoè.

In contradiction to the scientific name and an English vernacular name, this tree is not indigenous to Japan but is a native of central and northern China, and Korea. It is widely cultivated in temperate and subtropical regions, and rarely in highlands in the tropics.

The flower buds can be used for dyeing yellow or a beautiful granite-grey. The pods are rarely used for this purpose. In China and Vietnam this dye was only used to colour silk, embroidery thread and hat tassels, but not for other materials because of the many flower buds needed to prepare a dye-bath. Mixed with indigo, the dye gives a green colour. In Java, dried flower buds were imported from China for the batik industry. In the fine 'soga-batik' process they were used in the last fixing and colouring bath after the real colouring process, in a mixture together with rice flour, camphor, lime juice, sugar and water. Nowadays much cheaper synthetic dyes are used instead.
In temperate and subtropical regions the Japanese pagoda tree is commonly cultivated as an ornamental in gardens and parks, and as a road-side tree. The wood is durable and tough and can be used for window and door frames, and for implements.
Several medicinal uses have been reported. The flowers and pods possess styptic properties, and the pods can also be used to lower blood pressure. The plant may have oestrogenic activity.
The shoots, including the pods, seem to be suitable as fodder, but some plant parts, especially the pods and seeds, have been reported to be poisonous. In China an extract of the leaves and pods is used to adulterate opium. A gum similar to that from carob (Ceratonia siliqua L.) can be extracted from the seeds.

The Japanese pagoda tree is a source of rutin drugs. Flower buds contain an abundance of the pigment rutin (ca. 20% on dry weight base), which is a glycoside of quercetin and has a strengthening effect on capillary blood vessels. The flowers are bitter, astringent, but aromatic. In the pods kaempferol derivates have been demonstrated. In common with other Sophora species, several flavonoid and isoflavonoid compounds have been isolated from the pods, which in some cases have been held responsible for the poisoning of cattle, sheep and goats. The leaf protein concentrate, used as fodder, is a product relatively poor in protein and carotenoid pigments, and very rich in lipids.

A medium-sized, deciduous tree, up to 15(—25) m tall, with corrugated, dark greenish-brown bark and spreading branches. Leaves pinnately compound, 15—25 cm long; leaflets 9—15 per leaf, (narrowly) ovate, 2.5—5 cm x 1—2.5 cm, rounded at base, acute at apex. Flowers in terminal, 15—30 cm long panicles, yellowish-white; calyx 3—5 mm, corolla 12—15 mm long; stamens 10, more or less free. Fruit a 5—8 cm long pod, jointed, long-stalked, indehiscent and (1—)4—6-seeded. Seeds ellipsoid to nearly globose, yellowish-brown.
Seeds germinate quickly, usually within about 4 days. The plant is slow-growing, and usually starts flowering only when about 30—40 years old. Several cultivars are grown as ornamentals.

Japanese pagoda tree is well adapted to dry weather conditions and to a great variety of soils, and even waste land, but it thrives best in well-drained, sandy loam. It is a plant of temperate and subtropical regions, and cultivation in tropical regions is only possible at high altitudes.

Propagation can best be done by seeds, which should first be scarified and soaked. Grafting, layering and greenwood cuttings are used for ornamental cultivars.
Among the pests and diseases reported are leafminers such as Odontota dorsalis, aphids (Aphis spp.), and fungi such as Uromyces truncicola which cause a canker disease in seedlings.

Japanese pagoda tree is rarely used for dyeing nowadays. The labour required to collect enough flower buds to prepare a dye bath makes the product very expensive, and comparatively cheap synthetic dyes have taken over the place of the natural dye. The dye gives beautiful colours and was important in traditional handwork in several countries. Knowledge of this dye plant should be saved for the future, when a new interest in traditional dyes may develop.
Japanese pagoda tree has been advocated as a very suitable fuel tree because of its adaptability to various climates (even to dry climates) and to a great variety of soils, and also because it is capable of regrowth from stumps. However, its possibilities are limited in the tropics because of its ecological requirements.

Bean, W.J., 1980. Trees and shrubs hardy in the British Isles. 8th ed. revised. Vol. 4. John Murray, London. pp. 388—390, pl. 49.
Chadha, Y.R. (Editor), 1972. The wealth of India. Raw materials. Vol. 9. Publications & Information Directorate, Council of Scientific and Industrial Research, New Delhi. p. 434.
Crevost, Ch. & Pételot, A., 1941. Catalogue des produits de l'Indochine. Tome 6. Tannins et tinctoriaux. Gouvernement général de l'Indochine, Hanoi. p. 28.
González, G., Alzueta, C., Barro, C. & Salvador, A., 1988. Yield and composition of protein concentrate, press cake, green juice and solubles concentrate from wet fractination of Sophora japonica L. foliage. Animal Feed Science and Technology (Netherlands) 20: 177—188.

H. Sangat-Roemantyo & Wirdateti

Sangat-Roemantyo, H. & Wirdateti, 1991. Sophora japonica L.. In: Lemmens, R.H.M.J. and Wulijarni-Soetjipto, N. (Editors): Plant Resources of South-East Asia No 3: Dye and tannin-producing plants. PROSEA Foundation, Bogor, Indonesia. Database record: prota4u.org/prosea