Leadwood Tree, Ivory tree
Combretum imberbe

Family: Combretaceae

What it is like

Leadwood Tree or Ivory Tree, Combretum imberbe, is a tropical, slow-growing, deciduous tree of about 21 m tall. Its bark cracks in rectangular flakes and the young branches and twigs have hard spines. The simple, oblong leaves are arranged oppositely and silvery grey in colour with red scales. The flowers are yellowish-green in loose spikes and with four wings. Edible gum is obtained from the tree and used for confectionary. The leaves are eaten as green vegetable. Several plant parts are used in traditional medicine. In particular, roots and leaves are powdered or formed into decoction. Both forms are used in the treatment of stomach pains, diarrhoea, coughs and colds, and chest pains among others. Leaf decoction is used to treat constipation. Leaves are burnt and the smoke is inhaled for relief from coughs, colds, and chest pains. The root is used to treat infertility in women; the flowers for coughs; and bark powder for leprosy. Further, the bark is a source of tannins. Wood ash has high lime content and can be used as toothpaste and as substitute of whitewash. The wood is used for mortars, fence poles, toys, railway sleepers, etc. It burns slowly and with great heat, therefore used as a fuel and for charcoal making.

Combretum imberbe is a deciduous Tree growing to 10 m (32ft) by 10 m (32ft) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 10 and is frost tender. 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 and can grow in saline soils. It cannot grow in the shade. It prefers moist soil and can tolerate drought.

Height (m): 10

Where it is found

Open woodland and wooded savannah, especially along rivers; on a wide variety of soils from sandy to limestone outcrops, also on alluvial and black cotton soils, but only occasionally on heavy clay, from sea-level to 1,000 metres.

Southern and eastern Africa - Angola, Zimbabwe, Malawi, Tanzania, Mozambique, Namibia, Botswana, Zimbabwe, Swaziland and S. Africa.

Conservation Status: This taxon has not yet been assessed

Countries/locations it is found in

Found In: Africa, Angola, Australia, Botswana, Central Africa, East Africa, Malawi, Mozambique, Namibia, South Africa, Southern Africa, Swaziland, Tanzania, Zambia, Zimbabwe.

How it is used

Food

Rating: 2

Edible portion: Gum, Leaves, Fruit, gum. An edible gum is obtained from the tree. A rather clear gum of medium quality.

Gum: can be chewed as a chewing gum or can often be used as a sweetener or thickening agent in foods.

Medicine

Rating: 2

Several plant parts are used in traditional medicine. The powdered roots or leaves, and decoctions from the roots and leaves, are taken to treat stomach aches and diarrhoea; coughs and colds; chest pains etc. On the other hand, a leaf decoction is applied as an enema to treat constipation. The smoke of burnt leaves is inhaled as a remedy for coughs, colds and chest complaints. The roots are used to treat infertility in women. An infusion is drunk to treat schistosomiasis. The bark powder is applied externally as a treatment against leprosy. The flowers are used to make a cough medicine. Acetone and ethyl acetate extracts of the leaves have shown pronounced anti-inflammatory activity. An aqueous extract of the leaves has shown activity against Schistosoma haematobium. The pentacyclic triterpene, imberbic acid, has been isolated from the leaves; this compound has shown potent antibacterial activity against Mycobacterium fortuitum and Staphylococcus aureus.

Antibacterial: Kills bacteria.

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

Antiinflammatory: Reduces inflammation of joints, injuries etc.

Antitussive: Prevents or relieves coughing.

Laxative: Stimulates bowel movements in a fairly gentle manner.

Leprosy: Used to treat leprosy - a chronic bacterial infection of the skin and superficial nerves (in the skin) caused by Mycobacterium leprae.

Parasiticide: Treats external parasites such as ringworm This should perhaps be joined with Parasiticide in

Urinary: Treats urinary problems, including urinary tract infection (UTI).

Other

Rating: 4

Other Uses: The ash from the wood has a high lime content, and is sometimes used as toothpaste and as a substitute of whitewash to decorate walls of houses. In tests the wood ash has shown good results in managing cowpea weevils in stored cowpea seeds. The bark is a source of tannins. The heartwood is dark brown; it is distinctly demarcated from the thin layer of yellow-brown sapwood. The grain is straight, texture fine. The wood is very heavy and extremely durable, even in contact with the ground, and is very termite resistant. It is difficult to work, rapidly blunting cutting edges, but it takes a very nice lustrous polish. The turning properties are excellent. The wood is used for fence poles, mine props, railway sleepers, mortars, walking sticks, inlay work, toys and turnery. Because of its durability, it is commonly used for the main supporting poles of huts. It is popular for sculpture and lathe work, whereas it is also used to make heavy, extremely durable furniture. The wood is favoured for use as a fuel and for charcoal production; it burns slowly and with great heat.

Charcoal: Used for fuel, drawing, deodorant, filter, fertilizer etc.

Fuel: Usually wood, plant materials that have been mentioned as being a good fuel.

Furniture: A few miscellaneous uses that do not fit easily into other headings.

Gum: Gums have a wide range of uses, especially as stabilizers, emulsifiers, thickening agents, adhesives etc.

Insecticide: Kills insects.

Paint: Plants used directly as a paint. Does not include oil plants and dyes that can be used as ingredients in paints.

Parasiticide: Kills external body parasites such as hair lice.

Tannin: An astringent substance obtaied from plants, it is used medicinally, as a dye and mordant, stabilizer in pesticide etc.

Teeth: Plants used to clean and care for the teeth.

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

Coppice: A traditional method of woodland management which exploits the capacity of many species of trees to put out new shoots from their stump or roots if cut down.

How it is grown

A tropical plant. Plants are not tolerant of frosts. Grows best in a sunny position and a well-drained soil. Established trees are fairly drought resistant. A very slow growing tree. Under natural conditions, mean annual diameter increment rates of only 0.3 mm to 2 mm have been recorded, but under optimal conditions in cultivation young trees may reach 6 m tall in 15 years. The trees can become very old. Radiocarbon dating showed that some specimens were over 1,000 years old. Dead trees can remain upright for as much as 80 years.. Trees respond well to coppicing. The number of shoots produced from cut stems is negatively correlated with the height at which the trees are cut, but shorter shoots are produced when the tree is cut close to the ground. A cutting height of 1 metre appears most advantageous.

Propagating it: Seed - best sown when still fresh. Pre-soak in warm water for a few hours before pressing the seed into seedling trays filled with river sand. After they have been covered with a thin layer of sand, the seeds should be kept moist. They germinate in 1 - 2 weeks, but very low germination rates have been recorded (3 - 5%), as well as high mortality among seedlings. The seedlings can be transplanted into nursery bags after development of the second leaf. The seed of most, if not all, species can be stored inside the fruit for several years without losing viability.

Best place to grow:

Habit: Tree

Hardiness: 10-12

Growth: Slow

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

Shade: No shade

Moisture: Moist

Things to keep in mind

Its other names

Local names

Leadwood Tree or Ivory Tree, Combretum imberbe. Other Names: Hardekool, Impondozendhlovu, Lipholovu lendlovu, Loodhout, Mgodo, Mkolongonjo, Mnangali, Mocoza, Monzo, Motswere, Motswiri, Msimbiti, Muando, Muchenarota, Mukotama, Munangar, Munyondo, Mutsviri, Omukuku, Umtshenalotha, Umtshwili.

Synonyms

Argyrodendron petersii Klotzsch Combretum petersii Klotzsch Combretum primigenum Marloth ex Engl. Co