Benin Ebony
Diospyros crassiflora

Family: Ebenaceae

What it is like

Other common names include Gabon ebony, African ebony, and West African ebony. Diospyros crassiflora or Benin ebony is endemic to western Africa. It is slow-glowing, reaching about 25m in height with a cylindrical trunk that can be 120 cm in diameter and branchless for up to 15 m. It produces very hard, very dark, and durable heartwood which is highly demanded in the export market. It is used to make sculptures, pool cues, door knobs, musical instruments, carvings, etc. Bark decoction is used in the treatment of ovarian problems. It can also be used against yaws and sores.

Diospyros crassiflora is an evergreen Tree growing to 15 m (49ft) by 12 m (39ft) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 10. The plant is not self-fertile. 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 cannot grow in the shade. It prefers moist soil.

Height (m): 15

Where it is found

Usually found as isolated trees in lowland semi-deciduous and evergreen rain forest at elevations up to 1,000 metres, but usually avoiding the most humid forest types.

Western tropical Africa - Nigeria to the Central Africa Republic, south to Gabon and DR Congo.

Conservation Status: Status: Endangered A1d

Countries/locations it is found in

Cameroon; Central African Republic; Congo; Congo, The Democratic Republic of the; Gabon; Nigeria

How it is used

Food

Rating: 0

Medicine

Rating: 2

A decoction of the bark is taken in draught and by enema for treating ovarian troubles. The powdered bark is used, combined with the red heart-wood of Pterocarpus soyauxii, to treat yaws. It is also applied to sores, perhaps in similar context. Leaf-sap is instilled into the eyes for purulent ophthalmia. Examination of the roots on Nigerian material has shown a strong presence of alkaloids.

Ophthalmic: Treats eye complaints.

Skin: Plants used in miscellaneous treatments for the skin.

Other

Rating: 4

Other Uses: The heartwood is black, very hard, but appears only in older trees over a certain girth; it is clearly demarcated from the 5 - 12cm wide band of creamy to reddish yellow sapwood that produces bands of black. In Cameroon, where the tree attains a larger stature (25 metres high by 3 - 3.5 m in girth), the heartwood is said to be 95cm girth. The texture is fine; the grain straight or slightly interlocked. The wood is heavy, hard; very durable, being resistant to fungi, dry wood borers and termites. It seasons slowly, with a high risk of checking or distortion; once dry it is poorly stable in service. The wood is difficult to saw and work, with serious dulling effect on saws and cutting edges - stellite tipped and tungsten carbide tools are recommended; the surfaces take an excellent polish, but picking up of interlocked or curly grain may occur in planing and a reduced cutting angle is recommended; it has a tendency to split upon nailing, and pre-boring is advised; it has good slicing properties, but powerful machines are needed; the gluing properties are satisfactory. The heartwood is valued for black-wood cabinetry, furniture manufacture and high-class carpentry. It is also used for heavy flooring, interior trim, ship building, vehicle bodies, musical instruments (especially the black keys of pianos, but also guitar fingerboards), precision equipment, turnery, carvings, knife-handles and brush backs. The sapwood, and sometimes also the heartwood, is used for poles, posts, vehicle bodies, agricultural implements, toys, novelties, sporting goods, combs, ladders, boxes, crates, crossbows, veneer and plywood. The wood of young trees is flexible and is used locally to make crossbows. The wood is used for fuel.

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.

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

How it is grown

A slow-growing species. The mean diameter growth was 4.5mm per year for trees with a mean height of 14.5 metres and a mean age of 50 years. However, two trees measured over a period of 10 years in central Gabon had an average annual growth rate of only 1mm in diameter. In a 50-years-old plantation in Cameroon, dominant trees were on average 24 metres tall and 22cm in bole diameter, whereas the standing volume was estimated at 320 cubic metres/ha. In Benin the Ejagham recognise four sorts of tree: Nyareti is a 'female' tree yielding top quality ebony. Num nyareti is the 'male' of this with second grade ebony. Nyareh is 'female' with poor ebony but providing excellent fuel. Num nyareh is its 'male' yielding neither good ebony nor good fuel. Not all Diospyros species produce ebony, but in some a blackening appears on immersion in water for shorter or longer duration according to the species. The water also blackens. Such immersed timber loses its blackening on re-exposure to air and drying. The true blackening of ebony is the result of necrosis in very small spots. A dioecious species, both male and female forms need to be grown if fruit and seed are required. Bloom color: White/Near White.

Propagating it: Seed - it has a very short viability and so should be sown as soon as possible. The flesh should be removed since this contains germination inhibitors. Sow the seed in a shady position in a nursery seedbed. The sowing media for ebony uses soil and fine sand at the ratio 3:1. The seed is planted horizontally or vertically with the radicle end down, with a sowing depth of 1 - 1.5x the thickness of seed. Distance between the seeds is 3 - 5cm. Seeds are very sensitive to desiccation during germination and early growth, so must be regularly watered at this time. Normally the seed will germinate after one week. In one trial, fresh seed, sown one day after collection, showed 85% germination rate within 17 - 65 days. As a rule fresh seeds have a high percentage of fertility. The seedlings develop long taproots at an early stage, often before any appreciable elongation of the shoot takes place. The growth of the seedling is decidedly slow .

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

The sawdust may cause allergic contact dermatitis in wood workers.

Its other names

Local names

Gabon ebony, African ebony, West African ebony, Benin ebony

Synonyms

Diospyros ampullacea G?rke Diospyros evila Pierre ex A.Chev. Diospyros incarnata G?rke ex De Wild.