Protologue Rev. Int. Bot. Appl. Agric. Trop. 14: 876 (1934).
Family Mimosaceae (Leguminosae - Mimosoideae)
Chromosome number 2n = 26
Synonyms Acacia albida Delile (1813).
Vernacular names Apple-ring acacia, winter-thorn, white-thorn, ana-tree (En).
Arbre blanc, cad, faidherbier (Fr). Espinheiro de Angola (Po).
Mgunga, mkababu (Sw).
Origin and geographic distribution The origin of Faidherbia albida is unclear.
It has been postulated that it originated in the Sahara before desertification, but also that it
was originally a riverine tree of eastern and southern Africa that was introduced through
pastoralism and agriculture into western Africa, where it is only found on cultivated or
previously cultivated land. It has long been preserved and protected on croplands by African
farmers. However, this practice has become much less common in recent years. Faidherbia
albida occurs all across the African continent, encircling the central African forest massif,
from the Atlantic coast (Senegal, Gambia) to the Red Sea (Egypt, Sudan, Eritrea and
Somalia) and from there to South Africa, Lesotho, Namibia and Angola. Its northern limit is
not well defined because it occurs along watercourses and in areas where groundwater is
present (e.g. in south-western Morocco, mountain massifs in the Sahara, and along the Nile
in Egypt). Elsewhere, Faidherbia albida occurs in Yemen, Saudi Arabia, Israel, Jordan,
Lebanon, Syria and Iran, and has been introduced into Ascension Island, the Cape Verde
Islands, Cyprus, India, Pakistan and Peru.
Uses Faidherbia albida is an ideal multipurpose agroforestry tree that is widely
retained or planted in dry, densely populated areas of West and East Africa where fallow
periods have become very short or have disappeared. Its ‘inverted phenology’ (leafless
during the rainy season and in leaf during the dry season), and ability to fix nitrogen and
draw water and nutrients from deep soil layers, has a beneficial effect on the microclimate,
soil fertility and soil moisture for associated crops. It is therefore commonly intercropped
with annual crops, especially pearl millet and groundnuts. Leaves and pods are an excellent
fodder in the dry season. Branches are pruned more or less intensely by herdsmen for use as
fodder. Pods are sometimes also used as fodder for domestic animals. The wood is commonly used for handicraft and implements, and for the construction of
houses, barns and grain stores. It is not long lasting and is sometimes soaked in water for
several months to remove the sap and make it more resistant to insect attack. It is an
excellent firewood and can be converted into high quality charcoal. The spiny branches are
used for fencing fields. Bark and roots, alone or mixed with other components, are common ingredients of
traditional medicinal preparations for external or internal usage. These preparations are
prescribed for respiratory infections, sterility, digestive problems, dysentery, backache,
malaria, fever, heart and circulatory problems, dental infections and deafness. The bark is
also used for making beehives, for stuffing saddles and in hut construction. Soap is made
from the wood ash, which also has depilatory action. Pods can be used as fish bait. Seeds are
eaten during famine but require long and elaborate preparation. Faidherbia albida has
religious significance amongst some tribes, e.g. as a graveyard tree.
Properties The nutritional value of leaves, flowers and pods is excellent and they
constitute a fodder supplement rich in phosphorus, digestible proteins and carotene. The net
energy value is 6–7 MJ/kg dry matter for leaves and pods with 12–15% of digestible proteins
in leaves on a dry weight basis, and 6–11% in pods. The mineral content of the pods and
leaves is satisfactory except for a deficiency of sodium and the trace elements copper and
zinc. The pods also lack manganese. The bark is rich in tannins, ca. 28%, but pods contain
only 5%. An oil can be extracted from the seeds, with a yield of 3–10%. Faidherbia albida
extracts did not show antibiotic activity in pharmacological tests. The wood is a medium-weight hardwood. At 12% moisture content, the density is 580–710
kg/m³, modulus of elasticity 8600–9400 N/mm², compression parallel to grain 41-54 N/mm²,
shear 6.4 N/mm², cleavage 16–21N/mm tangential and Janka side hardness 3500–5200 N.
The rates of shrinkage from green to oven dry are 3.7–4.6% radial and 8.4–8.6% tangential,
which can be rated as average. The wood glues well and has excellent nailing properties. It
is possible to produce bleached chemical pulp from the wood for the paper industry, but the
quality is poor and the yields low. The energy value of the wood is about 19,750 kJ/kg, which
is considered excellent for use as firewood.
Description Medium-sized to fairly large tree up to 20(–30) m tall, with bole up to
100(–150) cm in diameter; bark smooth when young but becoming fissured and flaky with
age, brown to whitish-grey; branches with paired stipular, straight spines up to 3 cm long.
Leaves alternate, bipinnately compound; petiole 0.5–3.5 cm long, eglandular; rachis 3-7.5
cm long, with 2–12 pairs of pinnae with a gland at the junction of each pinna pair; pinna
rachis 2.5–5.5 cm long, with 6–23 pairs of leaflets; leaflets oblong, 2.5–12 mm × 0.7–5 mm,
glabrous to pubescent. Inflorescence a dense axillary spike 3.5–16 cm long, with a peduncle
2–4 cm long. Flowers bisexual, 5-merous, successively white, cream and then yellow, sessile
or with a pedicel up to 2 mm long; calyx up to 2 mm long; petals up to 3.5 mm long; stamens
numerous (usually 40–50), 4–6 mm long, connate for about 1 mm at base; ovary superior, 1-celled, pubescent, style filiform. Fruit an indehiscent, falcate or coiled pod 6–25(–35) cm ×
2–3.5(–6) cm, bright orange to reddish-brown, septate, 10–30-seeded. Seeds ellipsoid-lenticular, 9–11 mm × 6–8 mm, dark brown and shiny, with large central areole.
Other botanical information Faidherbia albida is often included in the genus
Acacia. It is distinct in having an eglandular petiole, basally connate filaments, eglandular
anthers, and peculiar pods. The separation into the monotypic genus Faidherbia is also
supported by its pollen structure and by its phenology: leafless in the wet season and leafy
in the dry season. The existence of two forms (‘races’) of Faidherbia albida has been
recorded for East Africa, differing mainly in the degree of pubescence. However, numerous
intermediate forms can be found in several regions. Populations in Ethiopia show more
similarity with those in West Africa than with those in nearby East Africa.
Anatomy Wood-anatomical description:
- Macroscopic characters:
Heartwood yellowish-white, sometimes dark brown in the heart of old trees, not clearly
demarcated from the sapwood. Grain interlocked. Texture coarse.
- Microscopic characters:
Growth rings absent or indistinct. Vessels diffuse, 2-5/mm², solitary or in radial multiples of
2–3, mean tangential diameter 100–200 µm; perforation plates simple; intervessel pits 7–10
µm. Fibres 800–1500 µm long, moderately thick-walled. Parenchyma in wide, slightly
sinuous bands. Rays 14–18/mm, 1–2-seriate, storied, entirely composed of procumbent
parenchyma cells. Crystals in the septate parenchyma bordering the fibres.
Growth and development The seedling first develops a taproot which can grow
down very deeply until it reaches an adequate supply of water. Only then does the young
stem start to grow. After 90 days, the taproot may attain a depth of 90 cm and the stem a
height of 30 cm. Humid zone provenances develop more extensive lateral rooting near the
soil surface, whereas trees in dry zones develop a more prominent taproot. In good
conditions, annual growth in height of young trees may be 1–1.5 m. The width of growth
rings varies from 1 mm to more than 20 mm.
The tree sheds its leaves at the beginning of the rainy season and comes into leaf again in
the dry season. The physiology controlling this process is not yet understood. Flowering
starts around the seventh year. The inflorescences appear about 2 months after the leaves.
The fruits mature about 3 months after flowering. They are relished by livestock and game,
including elephants, which may disperse the seeds. The seed coat is tough, waterproof and
leathery, and maintains seed viability for many years. The total lifespan of the tree is
generally 70–90 years. Faidherbia albida forms root nodules and fixes nitrogen with slow-growing Bradyrhizobium
spp. Nodulating bacteria and nodules have been found at great depth. Under experimental
conditions root nodules have also been found with Rhizobium spp. Mineral nutrition is
enhanced by symbiosis with endomycorrhizal fungi such as Glomus spp. and Gigaspora spp.
Symbiotic mycelia have been found up to 30 m deep in the soil, enabling recycling of
nutrients from such depths. A relationship between infection by root-knot nematodes,
Bradyrhizobium and endomycorrhizal fungi resulting in stimulation of the formation of N-fixing nodules has been found, but this observation needs further investigation.
Ecology Faidherbia albida occurs in a wide range of habitats from deciduous forest
(as in the Guinea zone), riparian forest, savanna woodland to sand dunes and depressions in
the desert where its roots can reach ground water. It grows in a wide range of climatic
conditions, but it needs a long and distinct dry season and access to permanent ground
water. Under natural conditions, it is found particularly in association with water, e.g. along
rivers and in gullies and ravines. Its prefers an annual rainfall of 500–800(––1000) mm, but
in Mediterranean climates with winter rains 100–400 mm are sufficient. In more humid
habitats it cannot compete with other vegetation. It occurs from sea level to 2000(–2500) m
altitude. Faidherbia albida prefers deep, light sandy to moderately heavy soils, but also
occurs on heavier soils, even clay soils. It tolerates waterlogging or flooding for several
months, as occurs along the Nile and in rice fields in Senegal.
Propagation and planting Under natural conditions, reproduction is by seed and
root suckers. In some regions (e.g. western and southern Africa) propagation by seed is the
rule, whereas in other regions (e.g. in the Middle East) suckers prevail. In Sudan, trees
reproduce equally well by seed or suckers.
Seeds can best be collected from nearly ripe fruits while still on the tree, as the fruits are
eaten by game and livestock almost as fast as they fall to the ground. Moreover, completely
ripe seeds are often infested with insects such as Bruchid beetles. Fruits are mechanically
hulled. Faidherbia albida has orthodox seeds. Green seeds do not store well and must be
sown at once, but ripe seeds can be stored after drying and treatment against insects either
at ambient temperature (for at least 3 years) or at 1–4°C (many years). Green seeds do not
need treatment before sowing, but ripe or stored seeds should be treated with sulphuric
acid, immersed in boiling water or scarified, after which germination rates of 75–100% after
30 days have been obtained. In the nursery, seeds are planted in polythene bags (30 cm high
and 8 cm in diameter). Watering 2 times a day is recommended. After 3–4 months,
seedlings are 15–30 cm tall and can be planted in the field. Spacing is usually 10 m × 10 m.
Tests in Burkina Faso have shown that vegetative propagation of Faidherbia albida by
cuttings is feasible, with a success rate of about 50% for coppice shoots and root cuttings. In
Mali, however, trials with cuttings showed little success. Micropropagation is still at an
experimental stage.
Management Faidherbia albida often occurs in a park-like vegetation named
‘Faidherbia parks’, especially in West Africa, where it is widely intercropped with annual
crops. Studies on the microclimate under Faidherbia albida trees demonstrated the
beneficial effects of this on cropping. In densities of 20–30 trees/ha, the potential
evapotranspiration decreases by 50% during the dry season and 10% during the wet season
compared with cropping without trees. The soil dries out more slowly. Faidherbia albida
slightly improves the internal cohesion and porosity of the soil, while soil organic and
biological characteristics are strongly improved. In Senegal, increases in total carbon (62%),
mineralizable carbon (73%), humus (40–47%) and total nitrogen (50%) have been
demonstrated under a Faidherbia albida canopy. Soil conductivity, pH, and cation reserves
were higher but the difference was not significant. However, the exchange capacity, the
assimilated phosphorus, and the biological activity of the soil were significantly increased.
The litter is of good quality.
It has been demonstrated that 45% of total nitrogen in the stem of young plants is the result
of nitrogen fixation.
Yields of millet are much higher under a Faidherbia albida canopy; increases of 50-150%
have been recorded. Results for sorghum, cotton, groundnut and maize are variable and
either positive or negative, depending on the study. The effect may depend on soil fertility;
when this is high, Faidherbia albida competes with the crops.
The main causes of mortality during the first year are accidental cutting during weeding of
the associated crops, and the failure to control browsing by goats and sheep after crop
harvesting. Protection against browsing is essential for at least the first 2 years after
planting, while the use of marker stakes may reduce damage during weeding. Two weedings
a year are essential for a period of 3 years to prevent young trees from being overtopped by
weeds. Later, pruning is necessary so that crop cultivation beneath the trees is easier.
Diseases and pests In Niger and Burkina Faso, the nematodes Meloidogyne
javanica and Meloidogyne incognita attack young plants in the nursery; older plants are
resistant. Cochineal insects may also cause damage in the nursery; treatment with
parathion is effective. Defoliating caterpillars (notably Crypsotidia conifera) are the main
pest of adult trees, defoliating trees in Nigeria and Zimbabwe by up to 50%. Infestation of
seeds is mainly due to larvae of Bruchid beetles. Parasitic plants, such as Agelanthus
dodoneifolius (DC.) Polhill & Wiens, and strangler figs, such as Ficus thonningii Blume,
may infect the trees, but cause little damage.
Yield Average annual production of organic matter, measured under some large
trees in Senegal, was about 100 kg/tree of leaves, 45 kg/tree of bark and small wood, and 125
kg/tree of fruits. Regular lopping reduces fruit production. The yield of fuelwood in adult
trees is about 0.1 m³/year.
Genetic resources Faidherbia albida was a priority species within the FAO project
'Genetic resources of trees for the improvement of life in arid and semiarid zones'
(1979-1985) concerning exploration, evaluation and conservation of genetic resources of dry
zone species in 16 countries in the Sahel and northern Sudan zones. Seed collection and
provenance trials have been carried out in many of these countries. The most
comprehensive collection of germplasm is at Centre National de Semences Forestières,
Ouagadougou, Burkina Faso, with 48 accessions.
Prospects In many parts of Africa, farmers have used Faidherbia albida in
agroforestry systems for a very long time, highly appreciating this truly multipurpose tree.
However, in many areas traditional knowledge of the benefits of this species has faded, and
its use is neglected. A new impetus is needed to maintain or restore the use of Faidherbia
albida in farming systems in the drier zones of tropical Africa, where it can help soil
productivity and enable more intensive land use, especially where increasing population
density is dangerously shortening fallow periods. More research is needed on genetic
improvement to provide farmers with good planting material. Trials are needed to
determine preferred spacings in agroforestry.
Major references • Brenan, J.P.M., 1983. Manual on taxonomy of Acacia species: present taxonomy of four species of Acacia (A. albida, A. senegal, A. nilotica, A. tortilis). FAO, Rome, Italy. 47 pp. • CAB International, 2000. Forestry Compendium: global module. CAB International, Wallingford, United Kingdom. CD-Rom. • Campa, C., Grignon, C., Gueye, M. & Hamon, S. (Editors), 1998. L’acacia au Sénégal. Actes de la reunion thematique sur l’acacia au Sénégal, Dakar, Sénégal, 3-5 decembre 1996. Editions de l’ORSTOM, Paris, France. 476 pp. • Charreau, C. & Vidal, P., 1965. Influence de l’Acacia albida Del. sur le sol, la nutrition minérale et les rendements des mils Pennisetum au Sénégal. L’Agronomie Tropicale 20: 600–625. • CTFT, 1988. Faidherbia albida (Del.) A. Chev. (Synonyme : Acacia albida Del.), Monographie. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 71 pp. • Depommier, D., 1996. Production fruitière et devenir des semences de Faidherbia albida. La part des insectes spermatophages et du bétail dans la régénération de l’espèce. Cahiers Scientifiques, Cirad-Forêt, Montpellier, France 12: 9–22. • Libert, C. & Eyog Matig, O., 1996. Faidherbia albida et production cotonnière, modification du régime hydrique et des paramètres de rendement du cotonnier sous couvert du parc arboré au Nord Cameroun. Cahiers Scientifiques, Cirad-Forêt, Montpellier, France 12: 103–123. • Poschen, P., 1986. An evaluation of the Acacia albida based agroforestry practices in the Hararghes Highlands of Eastern Ethiopia. Agroforestry Systems 4: 129–143. • Roupsard, O., Ferhi, A., Granier, A., Pallo, F., Depommier, D., Mallet, B., Joly, H.I. & Dreyer, E., 1999. Reverse phenology and dry-season water uptake by Faidherbia albida (Del.) A. Chev. in an agroforestry parkland of Sudanese west Africa. Functional Ecology 13: 460–472. • Vandenbeldt, R.J. (Editor), 1992. Faidherbia albida in the West African semi-arid tropics. Proceedings of a workshop, 22–26 April 1991, Niamey, Niger. ICRISAT, Patancheru, India & ICRAF, Nairobi, Kenya. 206 pp.
Other references • Ahmed, M.M.M., El Hag, F.M., Wahab, F.S. & Salih, S.F., 2001. Feeding strategies during dry summer for lactating desert goats in a rainfed area under tropical conditions. Small Ruminant Research 39: 161–169. • Bebawi, F.F. & Mohamed, S.M., 1982. Effects of irrigation frequency on germination and on root and shoot yields of Acacia species. Plant and Soil 65: 275–279. • Brenan, J.P.M., 1959. Leguminosae subfamily Mimosoideae. In: Hubbard, C.E. & Milne-Redhead, M.A. (Editors). Flora of Tropical East Africa. Crown Agents for Oversea Governments, London, United Kingdom. 173 pp. • Campa, C., Diouf, D., Ndoye, I. & Dreyfus, B., 2000. Differences in nitrogen metabolism of Faidherbia albida and other N2-fixing tropical woody acacias reflect habitat water availability. New Phytologist 147: 571–578. • Chamshama, S.A.O., Mugasha, A.G., Klovstad, A., Haveraaen, O. & Maliondo, S.M.S., 1998. Growth and yield of maize alley cropped with Leucaena leucocephala and Faidherbia albida in Morogoro, Tanzania. Agroforestry Systems 40: 215–225. • Cisse, M.I., 1992. The fodder role of Acacia albida Del.: extend of knowledge and prospects for future research. In: Vandenbeldt, R.J. (Editor). Faidherbia albida in the West African semi-arid tropics. Proceedings of a workshop, 22–26 April 1991, Niamey, Niger. 206 pp. (pp. 29–38). • Dalpé, Y., Diop, T.A., Plenchette, C. & Gueye, M., 2000. Glomales species associated with surface and deep rhizosphere of Faidherbia albida in Senegal. Mycorrhiza 10: 125–129. • Dancette, C. & Poulain, J.F., 1968. Influence de l’Acacia albida sur les facteurs pédoclimatiques et les rendements des cultures. Nouvelle contribution. IRAT, CNRA, Bambey, Sénégal. 45 pp. • Depommier, D., 1996. Structure, dynamique et fonctionnement des parcs à Faidherbia albida (Del.) A. Chev. Caractérisation et incidence des facteurs biophysiques et anthropiques sur l’aménagement et le devenir des parcs de Dossi et Watinoma, Burkina Faso. Thèse de doctorat de l’Université de Pierre et Marie Curie, Paris VI, France. 519 pp. • Duponnois, R., Senghor, K., Thioulouse, J. & Bâ, A.M., 1999. Susceptibility of several sahelian Acacia to Meloidogyne javanica (Treub) Chitw. Agroforestry Systems 46: 123–130. • Fagg, C.W., 1992. Germplasm collection of Faidherbia albida in eastern and southern Africa. In: Vandenbeldt, R.J. (Editor). Faidherbia albida in the West African semi-arid tropics. Proceedings of a workshop, 22–26 April 1991, Niamey, Niger. ICRISAT, Patancheru, India & ICRAF, Nairobi, Kenya. 206 pp. (pp. 19–24). • Fagg, C.W. & Barnes, R.D., 1990. African Acacias: study and acquisition of the genetic resources. Final report on Overseas Development Administration Research Scheme R.4348. Oxford Forestry Institute, Oxford, United Kingdom. 170 pp. • Fahn, A., Werker, E. & Baas, P., 1986. Wood anatomy and identification of trees and shrubs from Israel and adjacent regions. The Israel Academy of Sciences and Humanities, Jerusalem, Israel. 221 pp. • Harmand, J.M., Njiti, C.F., Brugiere, D., Jacotot, N. & Peltier, R., 1995. Plantations de Faidherbia albida au Nord Cameroun. Essais comparatifs de provenances et associations agroforestières. Cahiers Scientifiques, Cirad-Forêt, Montpellier, France 12: 269–282. • Jama, B. & Getahun, A., 1991. Intercropping Acacia albida with maize (Zea mays) and green gram (Phaseolus aureus) at Mtwapa, Coast Province, Kenya. Agroforestry Systems 14: 193–205. • Louppe, D., N’Dour, B. & Samba, S., 1988. Influence de Faidherbia albida sur l’arachide et le mil au Sénégal. Méthodologie de mesure et estimations des effets d’arbres émondés avec ou sans pacage d’animaux. Cahiers Scientifiques, Cirad-Forêt, Montpellier, France 12: 123–129. • Maiga, A., 1987. L’arbre dans les sytèmes agroforestiers traditionnels dans la province de Bazéga. Influence du karité, du néré et de l’Acacia albida sur le sorgho et le mil. Mémoire IRD, Ouaguadougou, Burkina Faso, RBET-CNRST. 83 pp. • Miehe, S., 1986. Acacia albida and other multipurpose trees on the farmlands in the Jebel Marra highlands, Western Darfur, Sudan. Agroforestry Systems 4(2): 89–119. • Ndoye, I., Gueye, M., Danso, S.K.A. & Dreyfus, B., 1995. Nitrogen fixation in Faidherbia albida, Acacia raddiana, Acacia senegal and Acacia seyal estimated using the 15N isotope dilution technique. Plant and Soil 173: 175–180. • Seignobos, C., 1996. Faidherbia albida, élément décrypteur d’agrosystèmes : l’exemple du Nord Cameroun. Cahiers Scientifiques, Cirad-Forêt, Montpellier, France 12: 153–173.
Sources of illustration • Brenan, J.P.M., 1970. Acacia Mill. In: Brenan, J.P.M. (Editor). Flora Zambesiaca. Volume 3, part 1. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. 153 pp. (p. 64).
Author(s)
| • | C. Bernard Rés. St. Raphaël, 89 Rue des 4 Vents, 34090 Montpellier, France |
Editors
| • | L.P.A. Oyen PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, the Netherlands | | • | R.H.M.J. Lemmens PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, the Netherlands |
Associate Editors
| • | S.D. Davis Centre for Economic Botany, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AE, United Kingdom | | • | M. Chauvet INRA Communication, 2 Place Viala, 34060 Montpellier, Cedex 1, France | | • | J.S. Siemonsma PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, the Netherlands |
Illustrator
| • | W. Wessel-Brand Biosystematics Group, Wageningen University, Generaal Foulkesweg 37, 6703 AH Wageningen, the Netherlands |
Photo Editor
| • | E. Boer PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, the Netherlands |
Correct citation of this article: Bernard, C., 2002. Faidherbia albida (Delile) A.Chev.. Record from Protabase. Oyen, L.P.A. & Lemmens, R.H.M.J. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, the Netherlands.
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Faidherbia albida – wild and planted
1, part of young shoot; 2, flowering branch; 3, flower; 4, fruit; 5, seed Redrawn and adapted by W. Wessel-Brand
parkland
tree in leaves in field with ripening sorghum
flowering tree
fruiting tree
fruits
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