Styphnolobium japonicum (L.) Schott

A deciduous, small to medium-sized tree up to 15(-30) m tall; bole generally short; bark surface corrugated, dark greenish-brown or dark grey-green and spreading branches, with paler lenticels; crown broad. Leaves arranged spirally, imparipinnate, 15-25 cm long; stipules early caducous; leaflets alternate to subopposite, 7-17, elliptical to ovate-lanceolate, 1.5-6 cm x 1-2.5 cm, acute or sometimes obtuse at apex, mucronate, glabrous or sparsely hairy above, short-haired below, shortly petiolulate; stipellae absent or small and setaceous. Flowers in a terminal, 15-35 cm long panicle, papilionaceous; bracteoles present; calyx 3-4 mm long; stamens 10, filaments joined near the base; ovary superior, pilose. Fruit an indehiscent pod, 3-12 cm x 7-12 mm, constricted between the seeds, stipitate, glabrous, beaked, 1-8-seeded. Seeds ellipsoid to nearly globose, 8 mm x 4-5 mm, yellowish-brown. Seedling with epigeal germination; cotyledons emergent; first few leaves imparipinnate or sometimes 1- or 3-foliolate.

The tree starts flowering when about 3-4 years old, though sometimes only when about 30 years old. In Vietnam, trees flower from May to August and fruit from September to November. In China, flowering is in August-September, fruiting in October-November.

The tree is well adapted to great variety of soils, and even waste land, but thrives best in well-drained, sandy loam.

Japanese pagoda tree is well adapted to dry weather conditions. Being native in temperate and subtropical regions, cultivation in the tropics is only possible in drier regions or at the higher altitudes. Under temperate conditions S. japonica is tolerant of heat and drought, whereas it also tolerates severe frost (up to -25 deg. C) except when young.

S. japonica is native to central and northern China and Korea, but now widely cultivated in temperate and subtropical regions of the world, and rarely in highlands in the tropics, in South-East Asia at least in Vietnam and Thailand.

Propagation can best be done by seeds, which should be scarified or treated with hot water and soaked before sowing. Seeds of S. japonica germinate quickly, usually within about 4 days. Under temperate conditions the seed germinates well and within a few days. Grafting, layering, greenwood and root cuttings are used for ornamental cultivars. Trees can be coppiced successfully.

Among the pests and diseases reported are leafminers such as Odontata dorsalis, aphids (Aphis spp.), and fungi such as Uromyces truncicola which cause a canker disease in seedlings.

Ornamental: 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. Several cultivars are grown as ornamentals.

Tannin or dyestuff: 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, embriodery 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. Timber: The wood is durable and tough and can be used for window and door frames, and for agricultural implements. Gum or resin: A gum similar to that from carob (Ceratonia siliqua L.) can be extracted from the seeds. Fodder: 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. Medicine: The flower buds of S. japonica are astringent and possess styptic properties. They are a reputed remedy for the prevention of various types of haemorrhages (e.g.) haemoptysis, epistaxis, metrorrhagia), haemorrhoids, and are useful for the treatment of hypertension. Flower buds and young pods are an important source of rutin, which has 'vitamin P'-like properties and is used in the treatment of conditions characterized by increased capillary permeability and fragility. An extracts from the pods is toxic, but also can be used to lower blood pressure. S. japonica is also reputed to show oestrogenic activity. Other products: In China, an extracts of the leaves and pods is used to adulterate opium.