Black Guarea
Leplaea thompsonii

Family: Meliaceae

What it is like

Grown in Western tropical Africa, Black Guarea or Leplaea thompsonii is a medium-sized to large evergreen, shade-bearer tree growing about 35 m in height, with a straight and cylindrical trunk of up to 105 cm in diameter and can be branchless for up to 20 m. It sometimes has buttresses at the base that are short and blunt. The tree is a dioecious species and can flower and produce fruits throughout the year. The bark is used in traditional medicine for kidney pain, postpartum bleeding, rheumatism, and leprosy. It is also used as fish poison. The wood dust may cause irritation to the skin and mucous membranes. The wood is ideal for house building, flooring, joinery, doors, cabinet, furniture, interior trim, veneer, plywood, etc.

Leplaea thompsonii is an evergreen Tree growing to 35 m (114ft) by 30 m (98ft) 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, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid and neutral soils. It can grow in full shade (deep woodland) semi-shade (light woodland) or no shade. It prefers moist soil.

Height (m): 35

Where it is found

A sub-canopy tree in lowland evergreen rainforest, usually primary forest. It is most common in moist evergreen forest, especially in undisturbed forest, but it occurs also in moister types of semi-deciduous forest.

Western tropical Africa - Liberia to Cameroon, south to Gabon, Congo and DR Congo.

Conservation Status: This taxon has not yet been assessed

Countries/locations it is found in

Gabon; Nigeria; Liberia; Congo, The Democratic Republic of the; Congo; Côte d'Ivoire; Central African Republic; Ghana; Cameroon

How it is used

Food

Rating: 0

Medicine

Rating: 2

The bark is used in traditional medicine. A decoction of the bark is applied as an enema to treat kidney pain, bleeding after childbirth, rheumatism and leprosy. A bark maceration is taken as a strong purgative.

Antirheumatic: Treats rheumatism.

Kidney: Used in the treatment of kidney diseases

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

Purgative: A drastic laxative causing a cleansing or watery evacuation of the bowels, usually with a griping pain.

Other

Rating: 4

Other Uses The heartwood is orangey brown when freshly cut, darkening to reddish brown upon exposure; it is usually distinctly demarcated from the 5 - 10cm wide band of paler sapwood. The grain is usually straight, sometimes interlocked; the texture fine; there is a slightly moire aspect. The wood is moderately heavy; moderately hard; moderately durable, being resistant to fungi and only occasionally attacked by termites and pinhole borers, but it is slightly more susceptible to attacks of powder-post beetles. It generally air dries fairly easily with little degrade, but has some tendency to checking during kiln drying; once dry it is stable in service. The wood is usually fairly easy to saw and work; it contains less silica than the wood of Leplaea cedrata, but is slightly more dense. It can be finished to a smooth surface, but there may be a slight tendency to pick up during planing of quarter-sawn material and some gum may appear at the surfaces. A cutting angle of 20° is recommended when interlocked grain is present. The wood holds nails and screws well, but may split upon nailing and pre-boring is recommended. It glues satisfactorily and takes paints, varnishes and stains well, but filling is recommended. The bending properties are usually moderate. The wood is . The heartwood is strongly resistant to impregnation, the sapwood permeable to moderately resistant. The wood is valued for house building, flooring, joinery, interior trim, panelling, doors, ship building, vehicle bodies, furniture, cabinet work, veneer and plywood. It is suitable for toys, novelties, boxes, crates, carving and turnery. Good-quality veneer can be produced by slicing. Traditionally, the wood is used for dugout canoes.

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.

Paper: Related to the entry for Fibre, these plants have been specifically mentioned for paper making.

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

How it is grown

Grows best in flat but well-drained sites. The tree is classified as a shade-bearer. In the forest, seedlings are most common in the shade, although generally less common than those of Leplaea cedrata. For proper development of seedlings, some opening of the forest canopy seems essential. Initial growth of seedlings is slow. When they are exposed to more sunlight after one year, growth may speed up. However, planted trees in Nigeria reached on average only 10 metres in height and 20 cm in diameter after 25 years, and it has been estimated that it takes about 200 years for Leplaea thompsonii trees to reach 100cm in bole diameter. Plants can flower and produce fruit all year round. A dioecious species, both male and female forms need to be grown if fruit and seed are required.

Propagating it: Seed - best sown as soon as it is ripe because it has a short viability. Germination is rather slow, taking 20 - 35 days. Seedlings are drought sensitive.

Best place to grow:

Habit: Tree

Hardiness: 10-12

Growth: Slow

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

Shade: Full shade, semi-shade, no shade

Moisture: Moist

Things to keep in mind

The wood dust may cause irritation to the skin and mucous membranes. The bark is used as a fish poison.

Its other names

Local names

Black Guarea

Synonyms

Guarea le-testui Pellegr. Guarea oyemensis Pellegr. Guarea thompsonii Sprague & Hutch.