Japanese sophora

Synonyms: Japanese styphnolobium, Styphnolobium japonicum (L.) Schot, Chinese Scholar Tree, Japanese Pagoda Tree, Japanese pagoda, Japanese acacia

Japanese sophora (Styphnolóbium japónicum) – a species of the genus Styphnolobium (Styphnolobium) of the family Fabaceae. Native to Japan and China. Cultivated in Europe, the USA, and in most Asian countries. In cultivation since 1747. In Ukraine it first appeared in the Nikitsky Botanical Garden in Crimea in 1814, afterwards spreading throughout Crimea, the Odessa and Kherson regions. It is one of the symbols of Beijing. Lives up to 150 years.

It is a tall tree up to 25 m in height with a broad, dense and lush rounded crown. Grows quickly; in youth it can grow up to 1 m per year. Bark on old trunks is dark gray and fissured. Young shoots are greenish-gray.

Root system broad, shallow.

Leaves alternate, 11.5-25 cm long, imparipinnate, dark green above, glaucous beneath. Each leaf has 3-8 pairs of longitudinal ovate leaflets. Leaflets 2-5 cm long and 8-25 mm wide, coriaceous, with an acute apex and a broadly cuneate base, attached by short pubescent petiolules. They turn yellow in autumn.

Blooms twice a year – in July and August. Flowers are borne in loose panicles reaching up to 35 cm in length. Flowers are yellow or greenish-white, fragrant, 1-1.5 cm long, bisexual. Blooms for about a month; individual flowers last 3-4 days. Begins flowering at 10-15 years.

Fruits – fleshy, indehiscent pods of cylindrical shape, 3-8 cm long, with distinct constrictions. At first the pods are greenish-brown, becoming reddish at maturity. They ripen in September-October and remain on the branches all winter. Each pod contains 2-6 oval seeds, slightly laterally compressed, dark brown, smooth, dull, 7-8 mm long and 5-6 mm wide. Seeds are immersed in a sticky yellowish-green pulp. Most seeds do not mature.

Hardiness zone: 5b (down to -28 °C)

Location: drought-tolerant, dislikes cold winds. Prefers clay loams and sandy soils. Can tolerate slight soil salinity. In nature grows in clearings and at the edges of valley and mountain forests.

Care: fertilize at the end of July. The fertilizer Kemira-Lux can be used. In spring additional watering can be applied until July.

Pruning: tolerates formative pruning well.

Propagation: propagated by seeds, cuttings, and suckers.

Uses: like other legumes, it can fix and accumulate nitrogen, so it can be used to enrich the soil. In landscape design it is planted singly and in groups. It looks excellent against a background of trees with crimson, yellow, or pale-green foliage. It is also attractive when leafless, when the tree is adorned by greenish young shoots and reddish-yellow long pods. Buds and fruits are used in medicine (the buds are used to obtain the preparation «Rutin», from the fruits a wound-healing tincture is made). In its native region the wood is used for parquet and furniture. A durable yellow dye can be obtained from dried buds, which is used for dyeing silk fabrics. A valuable honey plant.