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Holoptelea grandis (Hutch.) Mildbr.

Protologue
Notizbl. Bot. Gart. Berlin-Dahlem 8: 53 (1921).
Family
Ulmaceae
Chromosome number
2n = 28
Vernacular names
Orange-barked terminalia (En).
Origin and geographic distribution
Holoptelea grandis occurs from Côte d’Ivoire east to Sudan and Uganda and south to DR Congo and Cabinda (Angola).
Uses
The wood of Holoptelea grandis, sometimes traded as ‘cedar’, ‘kekele’, ‘mumuli’, ‘ayo’ and ‘beli’, is mainly used for construction, flooring, joinery, interior trim, furniture, ladders, toys, novelties, boxes, crates, food containers, tool handles, canoes, turnery, matches, hardboard and particleboard. It is suitable for ship building, mine props, railway sleepers, veneer, plywood and pulpwood. It is also used as firewood and for charcoal production.
Several plant parts are used in traditional medicine. In Nigeria macerations of roots and bark are applied as poultice for treating rheumatism. A bark infusion is drunk as an anthelmintic and the seeds are eaten as a laxative. In Côte d’Ivoire crushed leaves are applied as plaster to treat oedema and piles. The leaf sap is instilled into the eye to relief ophthalmia. In the Central African Republic washing the body with water mixed with pulped bark is considered to have a strengthening effect. Holoptelea grandis is sometimes planted as an ornamental and roadside tree.
Production and international trade
The timber is rarely traded internationally and is mainly used locally, but in several countries it figures on lists of timbers to be promoted.
Properties
The heartwood is creamy white to pale yellowish brown and indistinctly demarcated from the sapwood. The grain is straight to interlocked, texture moderately fine and even. The wood is slightly lustrous.
The wood is medium-weight, with a density of 625–700(–765) kg/m³ at 12% moisture content, and soft to fairly hard. It dries fairly rapidly and well, but careful drying is recommended, especially the usage of thinner piling sticks in air drying to avoid case-hardening and mild drying schedules in kiln drying. The shrinkage rates are quite high, from green to oven dry 4.0–4.8% radial and 7.5–9.8% tangential. Once dry, the wood is moderately stable in service. At 12% moisture content, the modulus of rupture is 105–147 N/mm², modulus of elasticity 10,000–14,900 N/mm², compression parallel to grain 49–64 N/mm², cleavage 14–20 N/mm and Chalais-Meudon side hardness 2.7–3.6.
The wood saws and works well with both hand and machine tools, with moderate blunting effect on cutting edges. Occasional picking up may occur in quarter-sawn material due to the presence of interlocked grain. The wood sands and finishes very well, and has good jointing and moulding properties. Nailing properties are variable, boring and mortising properties satisfactory. The wood glues and paints well. It is suitable for peeling and slicing.
The wood has a low to moderate durability. It is susceptible to fungal attacks and moderately susceptible to termite and marine borer attacks. The heartwood is moderately resistant to treatment with preservatives, sapwood is permeable. The wood has a reputation of burning slowly and evenly and therefore has been used for torches. The bark has an iodine-like smell, which is said to repel elephants.
Description
Deciduous medium-sized to large tree up to 50 m tall; bole branchless for up to 30 m, straight or slightly wavy, up to 120 cm diameter, slightly fluted at the base or with steep buttresses up to 3(–6) m high; bark surface smooth or rough, usually cracking longitudinally, greyish to yellowish or pale orange, inner bark hard, granular, yellowish brown with green outer layer; crown irregular, with branches drooping at tips; twigs corky, with many lenticels, glabrous. Leaves alternate, simple and entire; stipules linear, 3–5 mm long, short-hairy, caducous; petiole 0.5–1 cm long, blackish; blade ovate to elliptical, 5–18 cm × 3–9.5 cm, rounded to cordate at base, short-acuminate at apex, papery or slightly leathery, with many small whitish dots, rough to the tough, glabrous or hairy on veins beneath, pinnately veined with 5–8 pairs of lateral veins. Inflorescence a cyme up to 4 cm long, usually in the axils of fallen leaves, with few–many male flowers at base and few bisexual flowers higher up. Flowers unisexual or bisexual; pedicel slender, 4–8 mm long; tepals 4–6, 1–2 mm long; stamens 7–12, free; ovary superior, flattened, styles 2, spreading, 4–6 mm long, persistent; male flowers with rudimentary ovary. Fruit a rounded to obovoid winged nut (samara), 3.5–4.5 cm × 2.5–3.5 cm, with short stipe, with papery, radially veined wings with notch at apex, nut in lower half of the wings, 9–13 mm × 6–8 mm, 1-seeded. Seed flattened, c. 6 mm × 4 mm. Seedling with epigeal germination; hypocotyl 2.5–3.5 cm long, slightly hairy, epicotyl 1–2.5 cm long; cotyledons slightly fleshy, 2-lobed, shortly stalked; first two leaves opposite, distinctly toothed.
Other botanical information
Holoptelea comprises 2 species, one of them in tropical Africa and one in tropical Asia.
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); 26: intervessel pits medium (7–10 μm); 30: vessel-ray pits with distinct borders; similar to intervessel pits in size and shape throughout the ray cell; 31: vessel-ray pits with much reduced borders to apparently simple: pits rounded or angular; 42: mean tangential diameter of vessel lumina 100–200 μm; 47: 5–20 vessels per square millimetre; (56: tyloses common). Tracheids and fibres: 61: fibres with simple to minutely bordered pits; 66: non-septate fibres present; 69: fibres thin- to thick-walled; (70: fibres very thick-walled). Axial parenchyma: 78: axial parenchyma scanty paratracheal; 79: axial parenchyma vasicentric; 80: axial parenchyma aliform; 82: axial parenchyma winged-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. Rays: 97: ray width 1–3 cells; (98: larger rays commonly 4- to 10-seriate); (104: all ray cells procumbent); 106: body ray cells procumbent with one row of upright and/or square marginal cells; 115: 4–12 rays per mm. Storied structure: 118: all rays storied; 119: low rays storied, high rays non-storied; 120: axial parenchyma and/or vessel elements storied; 122: rays and/or axial elements irregularly storied. Mineral inclusions: (157: crystals in tyloses).
(E. Ebanyenle, P.E. Gasson & E.A. Wheeler)
Growth and development
Holoptelea grandis is a light-demanding species which grows rapidly. In Côte d’Ivoire trees usually flower in January and fruits mature in February–March when twigs are leafless. Fruiting mostly occurs on trees with a bole of at least 60 cm in diameter, but sometimes fruits can be observed in young trees with a bole of hardly over 18 cm in diameter. The fruits are dispersed by wind.
Ecology
In West and Central Africa Holoptelea grandis is most common in semi-deciduous forest, but it can also be found scattered in moist evergreen forest, riverine forest and sometimes even in savanna forest. It is most abundant in logged or otherwise disturbed forest, including burnt forest. In Côte d’Ivoire it has often been found together with Triplochiton scleroxylon K.Schum. In Uganda it occurs up to 1200 m altitude.
Propagation and planting
Holoptelea grandis is a pioneer species and seedlings and saplings are commonly found in canopy gaps and in abandoned agricultural fields. It produces a lot of fruits and natural regeneration readily occurs. For planting, it is propagated by fruits which are easily collected near fruiting trees. There are 13,200–15,400 fruits/kg. Fruits can be stored in a cool and dry place. It is recommended to sow fruits in seed beds and to transplant into pots later. Sowing can be done with the fruit wings still present; pretreatment before sowing is not necessary. Seeds germinate abundantly after 5–10 days.
Management
Holoptelea grandis requires tending during the initial growing stages until plants are established. In Uganda planting either in pure stands or with an intercrop of coffee or banana is recommended.
Yield
In DR Congo a bole of 17 m long with a diameter of 86 cm yielded 6.3 m³ of wood.
Handling after harvest
It is recommended to treat the logs with preservatives soon after felling.
Genetic resources
Holoptelea grandis is fairly widespread and common in many regions, and therefore unlikely to suffer from genetic erosion.
Prospects
Even though its commercial importance as timber tree is actually limited, Holoptelea grandis is a fast-growing tree with a potential to yield timber and fuel in a short time, and is probably of some commercial importance in the near future. It can be considered suitable for commercial plantations and agroforestry systems, also because it has prospects for use as a shade tree. Further research is however warranted on growth and management practices.
Major references
• ATIBT (Association Technique Internationale des Bois Tropicaux), 1986. Tropical timber atlas: Part 1 – Africa. ATIBT, Paris, France. 208 pp.
• 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., 2000. The useful plants of West Tropical Africa. 2nd Edition. Volume 5, Families S–Z, Addenda. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 686 pp.
• CIRAD Forestry Department, 2009. Holoptelea grandis. [Internet] Tropix 6.0. http://tropix.cirad.fr/ africa/kekele.pdf. Accessed December 2009.
• Fouarge, J. & Gérard, G., 1964. Bois du Mayumbe. Institut National pour l’Etude Agronomique du Congo (INEAC), Brussels, Belgium. 579 pp.
• Katende, A.B., Birnie, A. & Tengnäs, B., 1995. Useful trees and shrubs for Uganda: identification, propagation and management for agricultural and pastoral communities. Technical Handbook 10. Regional Soil Conservation Unit, Nairobi, Kenya. 710 pp.
• Oteng-Amoako, A.A. (Editor), 2006. 100 tropical African timber trees from Ghana: tree description and wood identification with notes on distribution, ecology, silviculture, ethnobotany and wood uses. 304 pp.
• Polhill, R.M., 1966. Ulmaceae. In: Hubbard, O.B.E. & Milne-Redhead, E. (Editors). Flora of Tropical East Africa. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. 15 pp.
• Takahashi, A., 1978. Compilation of data on the mechanical properties of foreign woods (part 3) Africa. Shimane University, Matsue, Japan. 248 pp.
• Vivien, J. & Faure, J.J., 1985. Arbres des forêts denses d’Afrique Centrale. Agence de Coopération Culturelle et Technique, Paris, France. 565 pp.
Other references
• Aké Assi, L., Abeye, J., Guinko, S., Riguet, R. & Bangavou, X., 1985. Médecine traditionnelle et pharmacopée - Contribution aux études ethnobotaniques et floristiques en République Centrafricaine. Agence de Coopération Culturelle et Technique, Paris, France. 140 pp.
• 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.
• Baker, J.G. & Wright, C.H., 1909–1913. Ulmaceae. In: Thiselton-Dyer, W.T. (Editor). Flora of tropical Africa. Volume 6(1). Lovell Reeve & Co., London, United Kingdom. pp. 441–649.
• 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.
• Eggeling, W.J. & Dale, I.R., 1951. The indigenous trees of the Uganda Protectorate. Government Printer, Entebbe, Uganda. 491 pp.
• Hauman, L., 1948. Ulmaceae. In: Robyns, W., Staner, P., De Wildeman, E., Germain, R., Gilbert, G., Hauman, L., Homès, M., Lebrun, J., Louis, J., Vanden Abeele, M. & Boutique, R. (Editors). Flore du Congo belge et du Ruanda-Urundi. Spermatophytes. Volume 1. Institut National pour l’Étude Agronomique du Congo belge, Brussels, Belgium. pp. 39–51.
• Irvine, F.R., 1961. Woody plants of Ghana, with special reference to their uses. Oxford University Press, London, United Kingdom. 868 pp.
• 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.
• Keay, R.W.J., 1958. Ulmaceae. In: Keay, R.W.J. (Editor). Flora of West Tropical Africa. Volume 1, part 2. 2nd Edition. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. pp. 590–593.
• Keay, R.W.J., 1989. Trees of Nigeria. A revised version of Nigerian trees (1960, 1964) by Keay, R.W.J., Onochie, C.F.A. & Stanfield, D.P. Clarendon Press, Oxford, United Kingdom. 476 pp.
• Laws, R.M., 1970. Elephants as agents of habitat and landscape change in East Africa. Oikos 21(1): 1–15.
• Letouzey, R., 1968. Ulmaceae. Flore du Cameroun. Volume 8. Muséum National d’Histoire Naturelle, Paris, France. pp. 3–65.
• 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.
• Ogunkunle, A.T.J. & Oladele, F.A., 2004. Ethnobotanical study of fuelwood and timber wood consumption and replenishment in Ogbomoso, Oyo State, Nigeria. Environmental Monitoring and Assessment 91(1–3): 223–236.
• Plumptre, A.J., 1996. Changes following 60 years of selective timber harvesting in the Budongo Forest Reserve, Uganda. Forest Ecology and Management 89(1–3): 101–113.
• Safou-Tchiamaa, R., de Jésoa, B., Akagahb, A.G., Sèbea, G. & Pétraud, M., 2007. A preliminary survey of the interfacial bonding of some tropical hardwoods towards succinic anhydride and 2 octen-1-yl succinic anhydride molecules: Impact of lignin and carbohydrate polymers structure on the chemical reactivity. Industrial Crops and Products 26(2): 173–184.
• Salzmann, U. & Hoelzmann, P., 2005. The Dahomey Gap: an abrupt climatically induced rain forest fragmentation in West Africa during the late Holocene. The Holocene 15(2): 190–199.
• Sokpon, N., 1995. Seedling survival and growth of three emergent trees: relationship to canopy closure in the natural semi-deciduous forest of Pobe, south-eastern Benin. Bulletin de la Société Royale de Botanique de Belgique 128(1): 3–12.
Sources of illustration
• 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.
Author(s)
E.A. Obeng
Forestry Research Institute of Ghana (FORIG), University P.O. Box 63, KNUST, Kumasi, Ghana


Editors
R.H.M.J. Lemmens
PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
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
Associate editors
E.A. Obeng
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:
Obeng, E.A., 2011. Holoptelea grandis (Hutch.) Mildbr. In: Lemmens, R.H.M.J., Louppe, D. & Oteng-Amoako, A.A. (Editors). Prota 7(2): Timbers/Bois d’œuvre 2. [CD-Rom]. PROTA, Wageningen, Netherlands.
Distribution Map wild


1, fruiting twig; 2, male flower; 3, bisexual flower.
Source: Flore analytique du Bénin



wood in transverse section


wood in tangential section


wood in radial section