Japanese Pagoda Tree, Scholar Tree

Sophora japonica

Physical Characteristics

Sophora japonica is a deciduous Tree growing to 20 m (65ft) by 20 m (65ft) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 5 and is not frost tender. It is in flower in September, and the seeds ripen in November. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. It can fix Nitrogen. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers moist soil and can tolerate drought. It can tolerate atmospheric pollution.

Distribution

E. Asia - N. China, Japan, Korea.

Habitats

Woodland Garden Canopy;

Edible Uses

Edible Parts: Flowers Leaves Edible Uses: Rutin Tea Young leaves and flowers - cooked[177, 183]. The leaves need to be cooked in three lots of water in order to remove the bitterness[179]. This will also remove most of the vitamins and minerals[K]. The leaves are a rich source of rutin, they contain much more than the usual commercial source, buckwheat (Fagopyrum esculentum)[174]. The ovaries, before the flowers open, contain up to 40% rutin[218]. A tea can be made from the young leaves and flowers[183]. An edible starch is obtained from the seed[183].

Medicinal Uses

Abortifacient Antibacterial Anticholesterolemic Antidiarrhoeal Antiinflammatory Antispasmodic Diuretic Emetic Emollient Epilepsy Febrifuge Hypotensive Purgative Skin Styptic Tonic This species is commonly used in Chinese medicine and is considered to be one of the 50 fundamental herbs[218]. It came second in a study of 250 potential antifertility agents[218]. Diuretic, emollient, febrifuge, tonic[11, 147, 174, 178]. The flowers and flower buds are antibacterial, anticholesterolemic, anti-inflammatory, antispasmodic, haemostatic and hypotensive[11, 147, 174, 176, 178, 218, 238, 279]. The ovaries, especially just before the plant flowers, are a rich source of rutin and this is a valuable hypotensive agent[218]. The buds, flowers and pods are concocted and used in the treatment of a variety of ailments[218] including internal haemorrhages, poor peripheral circulation, internal worms etc[238]. This remedy should not be prescribed for pregnant women[238]. The seedpods are abortifacient[218]. The seed is emetic and haemostatic[218]. It is used in the treatment of haemorrhoids, haematuria, uterine bleeding, constipation, stuffy sensation in the chest, dizziness, red eyes, headache and hypertension[176].It should be used with caution since it is toxic[218]. The leaves are laxative[218]. They are used in the treatment of epilepsy and convulsions[218]. A decoction of the stems is used in the treatment of piles, sore eyes and skin problems[218].

Known Hazards

The plant contains cytisine, which resembles nicotine and is similarly toxic[238].