Gilbertiodendron dewevrei (De Wild.) J.Léonard

Kew Species Profiles

General Description

A large, evergreen tree of the African tropical humid forest, Gilbertiodendron dewevrei is an example of a species that can grow gregariously. That is to say, numerous individuals may grow together in the absence, or virtual absence, of large trees of any other species. Consequently, there are areas of forest in the Congo basin that are dominated by G. dewevrei, sometimes in almost pure stands. A handful of other tropical African forest trees from the pea and bean family (Leguminosae; Fabaceae sensu APG III 2009), such as Cynometra alexandri and Julbernardia seretii, share this tendency to form forests dominated by a single species.

Species Profile

Geography and distribution

Gilbertiodendron dewevrei is found in Angola, Cameroon, Central African Republic, Congo, Democratic Republic of Congo, Equatorial Guinea and Gabon.

Description

Overview: A large tree of lowland humid African forest, Gilbertiodendron dewevrei is often found in swampy areas. Despite growing up to 45 m tall and 2 m in diameter, it does not have buttresses (woody fins at the base of the tree to help support it).

Leaves: The leaves are compound, with 2-5 pairs of leaflets and have conspicuous stipules (leaf-like appendages) at the base of the leaf stem. It is an evergreen species and replaces its leaves almost continuously throughout the year. The young leaf shoots are reddish-purple in colour.

Flowers: Each flower has two bracteoles, three stamens (male parts) and a single large bright red petal; a colour which does not occur often in the genus. Most other species of Gilbertiodendron have a single white petal.

The trees usually flower once a year, but sometimes they skip a year. All Gilbertiodendron dewevrei trees in the forest flower simultaneously; during flowering the air is filled with the scent of the flowers and the ground is covered in the red petals.

Explosive fruits

The woody pods (fruits) are large (up to 30 cm long), flattened and covered in brown hairs. There is usually a single longitudinal nerve along the pod face near the upper margin. When pods open at maturity, they do so with explosive force. Nevertheless, because the seeds are large and heavy, they do not travel far. It has been estimated that populations of Gilbertiodendron dewevrei migrate only about 100 m every 200-300 years through successful seed dispersal and germination.

Uses

The wood is used in west-central Africa for construction work (such as boat-building) and other forms of carpentry such as making agricultural tools, furniture and toys. In traditional medicine, a decoction of the bark is used to treat diarrhoea and dysentery and to heal sores. The seeds are eaten in times of food shortage; they are also eaten by forest rodents, elephants and gorillas.

This species at Kew

Dried and alcohol-preserved specimens of Gilbertiodendron dewevrei are held in Kew's Herbarium where they are available to researchers by appointment.

Specimens of the wood and bark are held in the Economic Botany Collection in the Sir Joseph Banks Building and are available to researchers by appointment.

Discoveries in Congo

During botanical inventory work in Congo (Kinshasa), Kew botanist Xander van der Burgt noted that local tribesmen constructed umbrellas from the large juvenile leaves of this species, sewing the leaflets together with climbing stems from other plants. He also noted that their children made toys out of the large seeds.

Kew's work on this genus

Kew scientist Xander van der Burgt has recently published an article on the Gilbertiodendron ogoouense species complex, in which eight new species are described and one species is reinstated and transferred to Gilbertiodendron .

Read the article on the Gilbertiodendron ogoouense species complex

Distribution

Angola, Cameroon, Central African Republic, Gabon

Ecology

Lowland humid forest.

Conservation

Not assessed according to IUCN Red List criteria, but this widespread species is likely to be of Least Concern (LC).

Caesalpiniaceae, Hutchinson and Dalziel. Flora of West Tropical Africa 1:2. 1958

Morphology General Habit

Forest tree, to 125 ft. high, with clear bole and no buttresses

Morphology General Bark

Bark yellowish-brown, scaly

Morphology Reproductive morphology Flowers Corolla

Petals wine-red

Ecology

Gregarious, often in swamp forest.

International Legume Database and Information Service

Conservation

Insufficiently known

Ecology

Africa: Guineo-Congolian forest.

Morphology General Habit

Perennial, Not climbing, Tree