Japanese Pagoda Tree, Scholar Tree
Sophora japonica
Family: Fabaceae or Leguminosae
What it is like
Bloom Color: White, Yellow. Main Bloom Time: Early summer, Late summer, Mid summer. Form: Rounded.
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.
Height (m): 20
Where it is found
Open country between 300 and 1000 metres in W. China.
E. Asia - N. China, Japan, Korea.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Young leaves and flowers - cooked. The leaves need to be cooked in three lots of water in order to remove the bitterness. This will also remove most of the vitamins and minerals. The leaves are a rich source of rutin, they contain much more than the usual commercial source, buckwheat (Fagopyrum esculentum). The ovaries, before the flowers open, contain up to 40% rutin. A tea can be made from the young leaves and flowers. An edible starch is obtained from the seed.
Rutin: often used as a food supplement.
Tea: the various herb teas that can be used in place of tea, plus the genuine article.
Medicine
Rating: 3
This species is commonly used in Chinese medicine and is considered to be one of the 50 fundamental herbs. It came second in a study of 250 potential antifertility agents. Diuretic, emollient, febrifuge, tonic. The flowers and flower buds are antibacterial, anticholesterolemic, anti-inflammatory, antispasmodic, haemostatic and hypotensive. The ovaries, especially just before the plant flowers, are a rich source of rutin and this is a valuable hypotensive agent. The buds, flowers and pods are concocted and used in the treatment of a variety of ailments including internal haemorrhages, poor peripheral circulation, internal worms etc. This remedy should not be prescribed for pregnant women. The seedpods are abortifacient. The seed is emetic and haemostatic. It is used in the treatment of haemorrhoids, haematuria, uterine bleeding, constipation, stuffy sensation in the chest, dizziness, red eyes, headache and hypertension.It should be used with caution since it is toxic. The leaves are laxative. They are used in the treatment of epilepsy and convulsions. A decoction of the stems is used in the treatment of piles, sore eyes and skin problems.
Abortifacient: Causes an abortion.
Antibacterial: Kills bacteria.
Anticholesterolemic: Prevents the build up of cholesterol.
Antidiarrhoeal: Provides symptomatic relief for diarrhoea. Also see Astringent.
Antiinflammatory: Reduces inflammation of joints, injuries etc.
Antispasmodic: Relaxes muscular spasms and cramps, calming nervous irritation.
Diuretic: Acts on the kidneys, promoting the flow of urine.
Emetic: Induces vomiting.
Emollient: Softens the skin, causing warmth and moisture.
Epilepsy: Used in the treatment of Epilepsy - a disorder in which nerve cell activity in the brain is disturbed, causing seizures.
Febrifuge: Reduces fevers.
Hypotensive: Reduces blood pressure, it is used in the treatment of high blood pressure
Purgative: A drastic laxative causing a cleansing or watery evacuation of the bowels, usually with a griping pain.
Skin: Plants used in miscellaneous treatments for the skin.
Styptic: An astringent that stops bleeding by contracting the blood vessels.
Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.
Other
Rating: 2
A yellow dye is obtained from the seedpods and the flowers. It is green when mixed with indigo. Wood - tough, light, strong, of superior quality. Used in carpentry.
Dye: Plants that provide dyes.
Wood: A list of the trees and shrubs that are noted for having useful wood.
Food Forest: Plants for Edible Forest Gardens and Food Forests.
Nitrogen Fixer: Plants that fix nitrogen in the soil
How it is grown
Landscape Uses:Firewood, Pest tolerant, Specimen, Street tree. Succeeds in a well-drained moderately fertile soil in full sun. Tolerates poor soils, atmospheric pollution, heat and, once established, drought. Hardy to about -25° when mature, but it can be damaged by severe frosts when it is young. A very ornamental and fast growing tree, it grows best in hot summers. It grows best in the warmer areas of the country where the wood will be more readily ripened and better able to withstand winter cold. Trees take 30 years to come into flower from seed., but they do not often ripen their seed in Britain. Cultivated in China for the rutin contained in its leaves and ovaries. Plants should be container-grown and planted out whilst young, older plants do not transplant well. Plants in this genus are notably resistant to honey fungus. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. Special Features: Not North American native, Attractive flowers or blooms. The plant is heat tolerant in zones 9 through 5. (Plant Hardiness Zones show how well plants withstand cold winter temperatures. Plant Heat Zones show when plants would start suffering from the heat. The Plant Heat Zone map is based on the number of "heat days" experienced in a given area where the temperature climbs to over 86 degrees F (30°C). At this temperature, many plants begin to suffer physiological damage. Heat Zones range from 1 (no heat days) to 12 (210 or more heat days). For example Heat Zone. 11-1 indicates that the plant is heat tolerant in zones 11 through 1.) For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. The plant growth habit is a standard with a non-suckering single trunk.
Propagating it: Seed - best sown as soon as it is ripe in a greenhouse. Pre-soak stored seed for 12 hours in hot (not boiling) water and sow in late winter in a greenhouse. Prick out the seedlings as soon as they are large enough to handle into individual pots in the greenhouse, and grow them on for 2 years under protected conditions. Plant them out into their permanent positions in early summer of their third year. Cuttings of young shoots with a heel, July/August in a frame. Air-layering.
Best place to grow: Woodland Garden Canopy;
Habit: Tree
Hardiness: 4-9
Growth: Fast
Soil: Light (sandy), medium, heavy (clay)
Shade: No shade
Moisture: Moist
Things to keep in mind
The plant contains cytosine, which resembles nicotine and is similarly toxic.
Its other names
Local names
Synonyms
Styphnolobium japonicum