PROTA homepage Prota 7(1): Timbers/Bois d’œuvre 1
Record display


Parkia bicolor A.Chev.

Protologue
Bull. Soc. Bot. France 55, mém. 8: 34 (1908).
Family
Mimosaceae (Leguminosae - Mimosoideae)
Chromosome number
2n = 24
Vernacular names
Faux néré (Fr).
Origin and geographic distribution
Parkia bicolor occurs from Guinea and Sierra Leone east to eastern DR Congo, and south through Gabon and Congo to Cabinda (Angola).
Uses
The wood (trade names: eseng, essang, lo) is used for planks, carpentry and canoes. It is also suitable for light construction, interior trim, joinery, furniture, cabinet work, shipbuilding, toys, novelties, implements, turnery, boxes, crates, matches, veneer, plywood, hardboard, particle board and pulpwood.
The fruit pulp is occasionally eaten and the fermented seeds serve as a condiment for seasoning sauces and soups, in the same way as those of African locust bean (Parkia biglobosa (Jacq.) R.Br. ex G.Don), although much less commonly so. The fruit is used as bait for fish and squirrels. The tree with its open, widely spreading crown is used as a shade tree for crops, and it is sometimes retained when cutting the forest for agricultural land.
Several parts of the tree are used in traditional medicine. A bark maceration is applied to treat eye complaints, a bark decoction to treat toothache, dried and powdered bark to enhance healing of wounds and sores, and a vapour bath of the bark to treat rheumatism. Leaf pulp is rubbed on smallpox and chicken pox. The roots serve to treat measles, infertility in women and sexually transmitted diseases.
Production and international trade
Although the wood of Parkia bicolor is often considered to be of inferior quality, it is locally marketed in Côte d’Ivoire and Cameroon, and probably also elsewhere.
Properties
The heartwood is pale yellow, sometimes with darker irregular streaks; it is indistinctly demarcated from the wide sapwood. The grain is variable, from straight to interlocked, texture coarse but even. The fresh wood has an unpleasant odour.
The wood is moderately light, with a density of 460–630 kg/m³ at 12% moisture content. It air dries rapidly, but distortion may occur. The rates of shrinkage are moderately high, from green to oven dry 2.6–5.3% radial and 7.5–9.6% tangential. The wood is moderately stable to unstable in service.
The wood is soft and moderately tough. At 12% moisture content, the modulus of rupture is 35–126 N/mm², modulus of elasticity 9500–11,600 N/mm², compression parallel to grain 34–44 N/mm², shear 6–7 N/mm², cleavage 18–26 N/mm, Janka side hardness 2470 N and Janka end hardness 3020 N.
The wood saws moderately well and works satisfactorily with both hand and machine tools. It can be planed to a smooth and lustrous surface, but the wood is difficult to polish and varnish. The nailing and gluing properties are satisfactory. It is not durable and liable to termite, pinhole borer and marine borer attacks. The heartwood is moderately resistant to treatment with preservatives, the sapwood is permeable.
The wood yields about 57% sulphate pulp and is considered suitable for the paper industry.
The seed oil has been analyzed and was found to be non-toxic. It resembles the seed oil from Parkia biglobosa. Arachidic acid is the most abundant fatty acid (slightly over 40%), other acids are behenic, stearic, palmitic, linoleic acids and the uncommon bicolargic acid (C21H38O2).
Preliminary phytochemical screening of the leaves demonstrated the presence of cardiac glycosides, tannins, alkaloids and steroids. The roots contain gallic acid, lichexanthone and lupeol. A root extract showed antibacterial activity.
Adulterations and substitutes
The timber of Parkia filicoidea Welw. ex Oliv. is similar to that of Parkia bicolor and is sometimes traded under the same names.
Description
Medium-sized to fairly large, briefly deciduous tree up to 40 m tall; bole cylindrical, usually straight but sometimes twisted or curved, up to 100(–150) cm in diameter, with thin and fairly spreading buttresses up to 3(–6) m high; bark surface smooth to rough or scaly, shallowly pitted, grey-white to dark brown, inner bark granular or fibrous, brown or pinkish; crown widely spreading, umbrella-shaped; young twigs densely reddish brown short-hairy. Leaves alternate, bipinnately compound, up to 35(–45) cm long; stipules needle-shaped, c. 5 mm long, caducous; petiole 5–10 cm long, swollen at base, above the base with an elliptical gland; rachis ribbed, reddish brown short-hairy, with 10–25 pairs of pinnae; leaflets in (20–)28–50(–55) pairs per pinna, opposite, narrowly oblong, 5–10(–15) mm × 1–2.5 mm, unequal at base, rounded to acute at apex, glabrous, only midrib prominent. Inflorescence a pendulous head arranged in a raceme; head 5.5–8 cm × 3–4.5 cm, pinkish red, consisting of 2 parts, basal part initially cylindrical, later depressed globose, apical part globose; peduncle 5–25(–40) cm long. Flowers bisexual or sterile, regular, 5-merous, sessile; bisexual flowers in apical part of head, calyx 7–11.5 mm long with long tube, corolla lobes slightly longer, fused at base but free for more than half their length, stamens 10, fused at base, c. 7 mm exserted, ovary superior, shortly stiped, style slender, slightly shorter than stamens; staminodial flowers at base of basal part of head, calyx c. 6 mm long, sterile stamens c. 20 mm exserted; nectar-secreting flowers between bisexual and staminodial flowers, calyx c. 5 mm long, stamens rudimentary, with nectar glands at base. Fruit a linear pod 25–45 cm × 1.5–3.5 cm, with stipe of 2–7 cm long, glabrous, yellow to brownish red or wine red, becoming black when old, with yellowish, mealy pulp, indehiscent, up to 25-seeded. Seeds ellipsoid, 11–15 mm × 7–10 mm, brown, with thin, membraneous seed coat. Seedling with epigeal germination; hypocotyl 5–7 cm long, epicotyl 5–10 cm long; cotyledons thick and fleshy, rounded at apex; first leaves alternate, with 2–3(–4) pairs of pinnae.
Other botanical information
Parkia comprises about 30 species and has a pantropical distribution. Only 3 species, all belonging to the section Parkia, occur in continental Africa, and a fourth in Madagascar. The Parkia species from continental Africa seem to be closely related, with Parkia filicoidea being the closest relative of Parkia bicolor. The wood of Parkia madagascariensis R.Vig. is used for construction and planks. This poorly known species from moist forest in northern Madagascar resembles Parkia bicolor in leaves and inflorescences, but differs in its broad, flattened pods (5–9 cm broad). Parkia timoriana (DC.) Merr. from tropical Asia has occasionally been planted in East and southern Africa, but only as an ornamental and not as a timber tree.
Anatomy
Wood-anatomical description (IAWA hardwood codes):
Growth rings: (1: growth ring boundaries distinct); (2: growth ring boundaries indistinct or absent). Vessels: 5: wood diffuse-porous; 13: simple perforation plates; 22: intervessel pits alternate; 23: shape of alternate pits polygonal; 25: intervessel pits small (4–7 μm); 26: intervessel pits medium (7–10 μm); 29: vestured pits; 30: vessel-ray pits with distinct borders; similar to intervessel pits in size and shape throughout the ray cell; 42: mean tangential diameter of vessel lumina 100–200 μm; 43: mean tangential diameter of vessel lumina 200 μm; (45: vessels of two distinct diameter classes, wood not ring-porous); 46: 5 vessels per square millimetre; (47: 5–20 vessels per square millimetre); 58: gums and other deposits in heartwood vessels. Tracheids and fibres: 61: fibres with simple to minutely bordered pits; 66: non-septate fibres present; 68: fibres very thin-walled; 69: fibres thin- to thick-walled. Axial parenchyma: (76: axial parenchyma diffuse); 80: axial parenchyma aliform; 81: axial parenchyma lozenge-aliform; 83: axial parenchyma confluent; (89: axial parenchyma in marginal or in seemingly marginal bands); 91: two cells per parenchyma strand; 92: four (3–4) cells per parenchyma strand; (93: eight (5–8) cells per parenchyma strand). Rays: 98: larger rays commonly 4- to 10-seriate; 104: all ray cells procumbent; 115: 4–12 rays per mm. Mineral inclusions: 136: prismatic crystals present; 142: prismatic crystals in chambered axial parenchyma cells.
(E. Ebanyenle, A.A. Oteng-Amoako & P. Baas)
Growth and development
Seedlings can become 1 m tall in the first year. In Côte d’Ivoire the mean annual growth in diameter is about 0.7 cm for trees with a diameter at breast height of 10–70 cm in natural forest stands, and 1.7 cm per year in 14-year-old plantations. The tree is deciduous after the rainy season, and new leaves develop in bronze-red flushes, immediately followed by the flowers still in the dry season. However, it has been reported from south-western Cameroon that new leaves develop after fruiting at the start of the rainy season. Individual trees flower for 6–8 weeks. At night, the sterile flowers near the base of the inflorescence produce abundant nectar, which attracts bats. The flowers are probably most commonly pollinated by these bats, but dormice and pottos have also been recorded as feeding on the nectar. Fruits develop in about 2 months. Monkeys, chimpanzees and gorillas feed on the fruit pulp, and may disperse the seeds. In Côte d’Ivoire fruiting occurs in February–March. Parkia bicolor does not nodulate.
Ecology
Parkia bicolor occurs in a range of forest types, from wet evergreen forest to dry semi-deciduous forest. However, it is most common in mixed, moist, lowland, semi-evergreen rainforest, especially in well-drained places, but it can also be found along creeks and rivers and in swamps. In Cameroon it is mainly found in rainforest in the coastal zone together with numerous Caesalpiniaceae species, but it extends along watercourses into moist semideciduous forest. It occurs in regions with mean annual rainfall of 2000–4000 mm, and with a dry season of up to 3 months. It is found up to 1200 m altitude. In some regions, e.g. in southern Côte d’Ivoire, it is one of the most frequent large trees. Regeneration is fairly common in secondary forest.
Propagation and planting
The 1000-seed weight is 300–500 g. The seed loses its viability rapidly and should be sown quickly. Removal of the seed coat improves germination. Germination occurs 4–10 days after sowing. The seedlings are sensitive to damping off. Young seedlings are often found close to the mother tree and tolerate some shade, but saplings are light demanders. Parkia bicolor is classified as a non-pioneer light demander.
Management
In Gabon Parkia bicolor is recorded as occurring in fairly low densities (on average 0.74 m³/ha of total wood volume), and this is also the case in south-western Cameroon (0.72 m³/ha). In Cameroon the minimum felling diameter is 60 cm.
Handling after harvest
After felling the logs should be removed from the forest rapidly or be treated with a preservative immediately, because they are liable to blue stain attack.
Genetic resources
There are no indications that Parkia bicolor is threatened by genetic erosion. It is not only widespread, but is also common in several regions and has a wide ecological adaptation, including secondary forest.
Prospects
Until recently the wood of Parkia bicolor was considered of inferior quality. Now that the stands of many commercial timber species have become depleted in many regions, it is becoming more important, especially for local construction and joinery, but presumably also for export in the future. Tests on its economic potential for veneer and plywood production seem worthwhile. Much research is still needed on growth rates, ecological requirements and management of natural stands on a sustainable basis.
Major references
• Bolza, E. & Keating, W.G., 1972. African timbers: the properties, uses and characteristics of 700 species. Division of Building Research, CSIRO, Melbourne, Australia. 710 pp.
• Burkill, H.M., 1995. The useful plants of West Tropical Africa. 2nd Edition. Volume 3, Families J–L. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 857 pp.
• de Saint-Aubin, G., 1963. La forêt du Gabon. Publication No 21 du Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 208 pp.
• Hopkins, H.C., 1983. The taxonomy, reproductive biology and economic potential of Parkia (Leguminosae: Mimosoideae) in Africa and Madagascar. Botanical Journal of the Linnean Society 87: 135–167.
• Hopkins, H.C. & White, F., 1984. The ecology and chorology of Parkia in Africa. Bulletin du Jardin Botanique National de Belgique 54: 235–266.
• Siepel, A., Poorter, L. & Hawthorne, W.D., 2004. Ecological profiles of large timber species. In: Poorter, L., Bongers, F., Kouamé, F.N. & Hawthorne, W.D. (Editors). Biodiversity of West African forests. An ecological atlas of woody plant species. CABI Publishing, CAB International, Wallingford, United Kingdom. pp. 391–445.
• Takahashi, A., 1978. Compilation of data on the mechanical properties of foreign woods (part 3) Africa. Shimane University, Matsue, Japan, 248 pp.
• Villiers, J.-F., 1989. Leguminosae - Mimosoideae. Flore du Gabon. Volume 31. Muséum National d’Histoire Naturelle, Paris, France. 185 pp.
• Voorhoeve, A.G., 1979. Liberian high forest trees. A systematic botanical study of the 75 most important or frequent high forest trees, with reference to numerous related species. Agricultural Research Reports 652, 2nd Impression. Centre for Agricultural Publishing and Documentation, Wageningen, Netherlands. 416 pp.
• Wilks, C. & Issembé, Y., 2000. Les arbres de la Guinée Equatoriale: Guide pratique d’identification: région continentale. Projet CUREF, Bata, Guinée Equatoriale. 546 pp.
Other references
• Aiyelaagbe, O.O., Ajaiyeoba, E.O. & Ekundayo, O., 1996. Studies on the seed oils of Parkia biglobosa and Parkia bicolor. Plant Foods for Human Nutrition 49(3): 229–233.
• Ajaiyeoba, E.O., 2002. Phytochemical and antibacterial properties of Parkia biglobosa and Parkia bicolor leaf extracts. African Journal of Biomedical Research 5: 125–129.
• Akoègninou, A., van der Burg, W.J. & van der Maesen, L.J.G. (Editors), 2006. Flore analytique du Bénin. Backhuys Publishers, Leiden, Netherlands. 1034 pp.
• Aubréville, A., 1959. La flore forestière de la Côte d’Ivoire. Deuxième édition révisée. Tome premier. Publication No 15. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 369 pp.
• Bouquet, A., 1969. Féticheurs et médecines traditionnelles du Congo (Brazzaville). Mémoires ORSTOM No 36. Office de la Recherche Scientifique et Technique Outre-Mer. Paris, France. 282 pp.
• de la Mensbruge, G., 1966. La germination et les plantules des essences arborées de la forêt dense humide de la Côte d’Ivoire. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 389 pp.
• Dupuy, B., 1998. Bases pour une sylviculture en forêt dense tropicale humide africaine. Document Forafri 4. Cirad, Montpellier, France. 328 pp.
• Durrieu de Madron, L., Favrichon, V., Dupuy, B., Bar-Hen, A. & Maître, H.-F., 1998. Croissance et productivité en forêt dense humide: bilan des expérimentations dans le dispositif d’Irobo, Côte d’Ivoire (1978–1990). Document Forafri 2. Cirad, Montpellier, France. 69 pp.
• Fotie, J., Nkengfack, A.E., Peter, M.G., Heydenreich, M. & Fomum, Z.T., 2004. Chemical constituents of the ethyl acetate extracts of the stem bark and fruits of Dichrostachys cinerea and the roots of Parkia bicolor. Bulletin of the Chemical Society of Ethiopia 18(1): 111–115.
• Gilbert, G. & Boutique, R., 1952. Mimosaceae. In: Robyns, W., Staner, P., Demaret, F., Germain, R., Gilbert, G., Hauman, L., Homès, M., Jurion, F., Lebrun, J., Vanden Abeele, M. & Boutique, R. (Editors). Flore du Congo belge et du Ruanda-Urundi. Spermatophytes. Volume 3. Institut National pour l’Étude Agronomique du Congo belge, Brussels, Belgium. pp. 137–233.
• Hawthorne, W.D., 1995. Ecological profiles of Ghanaian forest trees. Tropical Forestry Papers 29. Oxford Forestry Institute, Department of Plant Sciences, University of Oxford, United Kingdom. 345 pp.
• Hawthorne, W. & Jongkind, C., 2006. Woody plants of western African forests: a guide to the forest trees, shrubs and lianes from Senegal to Ghana. Kew Publishing, Royal Botanic Gardens, Kew, United Kingdom. 1023 pp.
• InsideWood, undated. [Internet] http://insidewood.lib.ncsu.edu/search/. Accessed May 2007.
• Luckow, M. & Hopkins, H.C.F., 1995. A cladistic analysis of Parkia (Leguminosae: Mimosoideae). American Journal of Botany 82(10): 1300–1320.
• Neuwinger, H.D., 2000. African traditional medicine: a dictionary of plant use and applications. Medpharm Scientific, Stuttgart, Germany. 589 pp.
• Normand, D. & Paquis, J., 1976. Manuel d’identification des bois commerciaux. Tome 2. Afrique guinéo-congolaise. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 335 pp.
• Raponda-Walker, A. & Sillans, R., 1961. Les plantes utiles du Gabon. Paul Lechevalier, Paris, France. 614 pp.
• Sabatie, B., 1989. Biosystématique et variance dans la flore camerounaise: cas de quelques espèces arborescentes écophylétiques. Thèse de Doctorat d’Etat Sciences Naturelles, Université de Yaoundé I, Yaoundé, Cameroon. 299 pp.
• Sprent, J.I., 2001. Nodulation in legumes. Royal Botanic Gardens, Kew, United Kingdom. 146 pp.
• Vivien, J. & Faure, J.J., 1985. Arbres des forêts denses d’Afrique Centrale. Agence de Coopération Culturelle et Technique, Paris, France. 565 pp.
• White, L. & Abernethy, K., 1997. A guide to the vegetation of the Lopé Reserve, Gabon. 2nd edition. Wildlife Conservation Society, New York, United States. 224 pp.
Sources of illustration
• Voorhoeve, A.G., 1979. Liberian high forest trees. A systematic botanical study of the 75 most important or frequent high forest trees, with reference to numerous related species. Agricultural Research Reports 652, 2nd Impression. Centre for Agricultural Publishing and Documentation, Wageningen, Netherlands. 416 pp.
• Wilks, C. & Issembé, Y., 2000. Les arbres de la Guinée Equatoriale: Guide pratique d’identification: région continentale. Projet CUREF, Bata, Guinée Equatoriale. 546 pp.
Author(s)
A.T. Tchinda
Institut de Recherches Médicales et d’Etudes des Plantes Médicinales (IMPM), Ministère de la Recherche Scientifique et de l’Innovation, B.P. 6163, Yaoundé, Cameroun


Editors
D. Louppe
CIRAD, Département Environnements et Sociétés, Cirad es-dir, Campus international de Baillarguet, TA C-DIR / B (Bât. C, Bur. 113), 34398 Montpellier Cedex 5, France
A.A. Oteng-Amoako
Forestry Research Institute of Ghana (FORIG), University P.O. Box 63, KNUST, Kumasi, Ghana
M. Brink
PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
General editors
R.H.M.J. Lemmens
PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
L.P.A. Oyen
PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
J.R. Cobbinah
Forestry Research Institute of Ghana (FORIG), University P.O. Box 63, KNUST, Kumasi, Ghana
Photo editor
G.H. Schmelzer
PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands

Correct citation of this article:
Tchinda, A.T., 2008. Parkia bicolor A.Chev. In: Louppe, D., Oteng-Amoako, A.A. & Brink, M. (Editors). Prota 7(1): Timbers/Bois d’œuvre 1. [CD-Rom]. PROTA, Wageningen, Netherlands.

















































Distribution Map wild


1, base of bole; 2, leaf; 3, flowering branch; 4, fruit.
Redrawn and adapted by Achmad Satiri Nurhaman



bole


base of bole


bole


leafy branches


infructescence


infructescence


wood in transverse section


wood in tangential section


wood in radial section


transverse surface of wood