Clearing Nut
Strychnos potatorum

Family: Loganiaceae

What it is like

Strychnos potatorum or Clearing Nut Tree is a deciduous tree reaching a height of up to 12 m upon maturity. It is well-branched, with bole growing up to 100 cm in diameter. It is highly tolerant to drought when fully grown. The bark is pale gray. The leaves are glossy, green, oval and thin. The flowers are white to yellow green and occur in clusters. The fruits are round, smooth, and softly fleshy. Crushed fruits and bark are both used as fish poison. Young fruits are occasionally consumed as food. Medicinally, the leaves are used in the treatment of epilepsy and eye pain. The roots are aphrodisiac and used against cold and venereal diseases. Root and leaf decoction is used for coughs. The seeds have a wide range of medicinal treatment against liver and kidney problems, stomach problems, gonorrhea, leucorrhea, bronchitis, chronic diarrhea, diabetes, and many others. The wood is not suitable for carving but is ideal for carts, shafts, agricultural implements, tool handles, etc.

Strychnos potatorum is a deciduous Tree growing to 12 m (39ft) by 12 m (39ft) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 10. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in full shade (deep woodland) or semi-shade (light woodland). It prefers dry or moist soil and can tolerate drought.

Height (m): 12

Where it is found

In gallery forest, in Brachystegia woodland, semi evergreen bushland, often on river banks, on banks of dry riverbeds, or on termitaries from sea level to elevations of 1,600 metres.

E. Asia - India, Myanmar. Tropical Africa - DR Congo to Tanzania, south to northern S. Africa.

Conservation Status: This taxon has not yet been assessed

Countries/locations it is found in

Burundi; Congo, The Democratic Republic of the; India?; Malawi; Namibia; Rwanda, Africa, Asia, Botswana, East Africa, India, Malawi, Mozambique, South Africa, Southern Africa, Zambia, Zimbabwe.

How it is used

Food

Rating: 2

Young fruits - occasionally eaten or made into preserves. The pulp is eaten. They are an ingredient of 'Raja's Cup', an Ayurvedic coffee substitute. The fruit is a sub-globose berry 12 - 18mm in diameter with a firm pericarp, black when ripe, containing 1 - 2 seeds in a whitish pulp.

Coffee: the various substitutes that can be used instead of coffee.

Medicine

Rating: 2

The pounded leaves are used to treat watering and aching eyes. A decoction is taken to treat epilepsy The roots are aphrodisiac. The vapour of a root decoction is inhaled to treat colds and venereal diseases. A decoction of the roots and leaves is taken to treat cough. The seeds are used for the treatment of a range of complaints including those affecting the liver, kidneys and stomach; gonorrhoea, leucorrhoea, bronchitis, chronic diarrhoea, strangury, kidney and bladder stones, diabetes and eye diseases. The plant contains many monomeric and dimeric indole alkaloids, the root bark being especially rich. The monoterpene alkaloid cantleyine, isolated from the root bark, has shown a relaxing effect on isolated tracheal smooth muscles and may be the active ingredient responsible for the anti-cough and anti-asthmatic activity. Normacusine B, a monomeric alkaloid of the corynanthe class, also found in Rauvolfia, Tabernaemontana and Vinca spp., is sympatholytic and its hypotensive activity is stronger than that of reserpine, which is commonly used against high blood pressure. The total alkaloid extracts of the seeds, bark and leaves showed strychnine-like activity in vivo, had marked hypotensive effect and exhibited a depressant action on isolated heart muscle. In-vivo tests using the seed powder and an aqueous extract of the seeds prevented ulcer formation by decreasing acid secretory activity and increasing the mucin activity. An aqueous extract of the seeds has shown significant hepatoprotective activity. A methanol extract of the seeds had a diuretic effect and an antidiarrhoeal activity on castor oil-induced diarrhoea.

Antiasthmatic: Treats asthma.

Antidiarrhoeal: Provides symptomatic relief for diarrhoea. Also see Astringent.

Antitussive: Prevents or relieves coughing.

Aphrodisiac: Increases the sexual appetite.

Cardiac: Used in the treatment of heart problems.

Diuretic: Acts on the kidneys, promoting the flow of urine.

Epilepsy: Used in the treatment of Epilepsy - a disorder in which nerve cell activity in the brain is disturbed, causing seizures.

Hypotensive: Reduces blood pressure, it is used in the treatment of high blood pressure

Kidney: Used in the treatment of kidney diseases

Ophthalmic: Treats eye complaints.

Other

Rating: 4

Other Uses: The cut seeds are rubbed around the insides of a rough earthenware vessel and water is then placed in the vessel. This causes most of the impurities in the water to sink to the bottom after a while so that the clean(er!) water can be poured off. The seeds contain polyelectrolytes which can be used as coagulants to clarify turbid waters. In laboratory tests, direct filtration of turbid surface water with the seeds as a coagulant, produced a substantial improvement in its aesthetic and microbiological quality. The yellowish-grey wood has conspicuous white markings. It is close-grained, very hard and termite resistant, but splits easily and is therefore not suitable for carving. It is used to make carts, shafts, agricultural implements, tool handles etc.

Filter: Used to strain out particles from liquids.

Wood: A list of the trees and shrubs that are noted for having useful wood.

How it is grown

A shade-bearing tree, growing up well under the canopy of deciduous forest. Established trees are very drought tolerant. The plant produces root suckers.

Propagating it: Seed - the seedling quickly produces a soft, delicate taproot so the seed should be sown in deep, individual containers or in situ. Cuttings of half ripe wood. Root suckers.

Best place to grow:

Habit: Tree

Hardiness: 10-12

Growth: Slow

Soil: Light (sandy), medium, heavy (clay)

Shade: Full shade, semi-shade

Moisture: Dry, moist

Things to keep in mind

The pounded fruits are used as fish poison. The crushed bark is used as a fish poison.

Its other names

Local names

Ambu-prasada, Chillachettu, Chilladabeeja, Chillaginjalu, Chilu, Clearing nut, Dupa, Gajrah, Induga, Indupachettu, Iriya, Kataka, Katakami, Kotaku, Kuchla, M'tupa, Mitupe, Neimal, Nelmal, Nirmali, Tetan-kotai, Tetran-paral, Tetta, Tettamparel, Tettan cottay marum, Tettran, Toillaghenjaloo, Water-filter nut, chilla, chillikavi, cleaning nuts, clearing nut, clearing-nut tree, clearing-nut-tree, grape strychnos, ingini, kataka, kataka (seed), katakam, kottai, nirmal, nirmali, nirmaliträd, payah prasadisa, tetramabaral.

Synonyms

Strychnos stuhlmannii Gilg