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Blunting Effect Boring Carving Common Names Common Uses Countries of Distribution Cutting Resistance Distribution Overview Drying Defects Ease of Drying Environmental Profile Family Name Gluing Grain Heartwood Color Kiln Drying Rate Kiln Schedules Luster Mortising Moulding Movement in Service Nailing Natural Durability Numerical Data Odor Planing Polishing Product Sources References Regions of Distribution Resistance to Impregnation Response to Hand Tools Routing & Recessing Sanding Sapwood Color Scientific Name Screwing Silica Content Staining Steam Bending Strength Properties Substitutes Synonyms Texture Toxicity Trade Name Tree Identification Tree Size Turning Veneering Qualities		Scientific Name Celtis mildbraedii Trade Name African celtis Family Name Ulmaceae Synonyms Celtis usambarensis Common Names African celtis, Akpula, Asan, Atako, Ba, Bolunde, Bolwe, Busoga, Celtis, Esa, Esa-fufu, Esa-kokoo, Esa-pa, Gombe, Gombi, Isa, Isa fufuo, Ita, Ita gidi, Ita-gangan, Ita-ita, Itako, Kabaranga, Kalulu, Kayombo, Kiambo, Killiakamba, Lufugo, Luniumbo, Luniumbu, Mengo, Mgua, Mudengwa, Mukokukoma, Mukomakoma, Namanuka, Odu, Odu elias, Ohia, Ohia noleghe, Ohianameme, Omoin, Shiunza, Tongo, Uta, Yisa Regions of Distribution Africa Countries of Distribution  [VIEW MAP] Angola, Cameroon, Ghana, Ivory Coast, Kenya, Liberia, Nigeria, Sudan, Tanzania, Uganda, Zaire Common Uses Agricultural implements, Boat building (general), Boxes and crates, Building construction, Building materials, Domestic flooring, Flooring, Form work, Fuelwood, Furniture , Furniture, Heavy construction, Hockey sticks, Interior construction, Joinery, Light construction, Millwork, Mine timbers, Moldings, Particleboard, Plywood, Poles, Posts, Railroad ties, Skis, Sporting Goods, Stairworks, Tool handles, Turnery, Vehicle parts, Veneer, Veneer: decorative Environmental Profile The environmental status of this species within its natural growth range has not been officially assessed Distribution Overview Throughout much of tropical Africa from the Ivory Coast to Sudan, then south to Angola and Tanzania. Tends to grow in the semi-deciduous, moist, dense forests and transition zones. Heartwood Color Brown Red Pink Yellow Purple Green/grey White to cream Yellow to golden-yellow to orange Greenish to greyish Pale brown Freshly-Cut wood yellowish-white to light beige in color, but it turns to greyish beige upon exposure. Discoloration by fungi is a common feature. Sapwood Color Red Brown Yellow Same as heartwood White to yellow Grain Figure Other (figure) Interlocked Straight Even Distinct (figure) Irregular Other figure Interlocked Straight Distinct figure Irregular Generally straight, but not always Texture Medium Fine Even or uniform Uniform Fine Fine to medium Uniform Medium Luster Lustrous Pronounced Natural Durability Perishable Non-durable Non-resistant to powder post beetles Susceptible to insect attack The sapwood is susceptible to wood staining fungal attack Susceptible to attack from powder post (Lyctid & Bostrychid) beetles Perishable Susceptible to attack from termites (Isoptera) Non durable Pinworms (ambrosia beetles) often present in the standing tree Pinworms (ambrosia beetles) may be present in the felled log Pinworms (ambrosia beetles) are commonly present Susceptible to attack by fungi and termites Sapwood susceptible to attack by powder post beetles Felled logs are susceptible to attack by longhorn beetles The wood is highly vulnerable to fungal staining, and requires immediate preventive measures after sawing Odor No specific smell or taste Silica Content African celtis is reported to contain silica, but amounts are usually too low (less than 0.05% of ovendry weight) to affect machining operations. Toxicity Sawdust can cause irritation in some individuals Kiln Schedules Drying (speed) is fast Kiln Drying Rate (in days) is rather slow Kiln Drying Rate (in days) is fairly rapid Dry at a moderate speed Drying Defects Distortion Splitting Slight end splitting Moderate end spitting Slight cupping Slight twist/warp Discoloration Interlocked grain may cause distortion Ease of Drying Fairly Easy Slowly Rapidly Reconditioning Treatement Little degrade Controlled drying conditions will prevent rapid drying and yield best results. Kiln Drying Rate Naturally dries slowly Naturally dries quickly Rapid Naturally dries at a moderate speed Drying rate is fairly rapid to fast Slow (18-28 days for boards < 32 mm, to 52-84 days for boards >= 63 mm) Fairly rapid (11-17 days for boards under 32 mm, to 31-51 days for boards greater than 63 mm) Tree Identification Bole/stem form is buttressed Bole/stem form is straight Bole/stem form is cylindrical Tree Size Tree height is 40-50 m Bole length is 20-30 m Bole length is 10-20 m Tree height is 50-60 m Tree height is 60-70 m Trunk diameter is 100-150 cm Trunk diameter is 150-200 cm Product Sources Primary exporting countries are Ghana and Ivory Coast. Although current production is limited because of low demand, it could be increased substantially since the species is abundant and is widely distributed. Substitutes Except for steam bending application, African celtis is suggested as a potential substitute for Ash (Fraxinus). It is also considered to be a good flooring timber that wears smoothly Blunting Effect Moderate Blunting effect on machining is moderate Blunting effect on machining is slight Boring Fairly easy to very easy Fair to good results Carving Fair to Good Results Fairly Easy to Very Easy Cutting Resistance Easy to saw Cutting Resistance with dry wood is easy Cutting Resistance with dry wood is difficult Resistance to hand feeding in band-sawing and rip-sawing is rather considerable. Break-out at bottom and back of cut is also common during cross-cutting Gluing Fairly Easy to Very Easy Fair to Good Results Easy to glue Glues well Mortising Fairly Easy to Very Easy Fair to Good Results Moulding Fairly Easy to Very Easy Fair to Good Results Very Good to Excellent Results Movement in Service Fair to Good Stability - Medium Movement Unstable with Poor Stability - Large Movement Medium Small Nailing Fairly Easy to Very Easy Fair to Good Results Very Good to Excellent Results Poor to Very Poor Results Difficult to nail Pre-boring recommended Easy to nail Planing Fair to Good Results Fairly Easy to Very Easy A reduced cutting angle of 15 degrees is recommended in planing material containing interlocked and irregular grain Resistance to Impregnation Resistant sapwood Resistant heartwood Heartwood is moderately resistant Sapwood is permeable Response to Hand Tools Easy to Work Responds Readily Easy to machine Variable qualities Difficult to machine Routing & Recessing Fair to Good Results Fairly Easy to Very Easy Sanding Fair to Good Results Very Good to Excellent Results Screwing Very Good to Excellent Results Fair to Good Results Turning Fair to Good Results Fairly Easy to Very Easy Veneering Qualities Suitable for peeling Veneers easily Veneers moderately easy There is slight to moderate drying degrade and the potential for buckles and splits Logs slice and peel readily into veneer after steaming at a temperature of about 185 degrees F (85 degrees C). Satisfactory gluing is accomplished with urea or phenol glue types Steam Bending Moderate Polishing Fair to Good Results Very Good to Excellent Results Satisfactory results Good results Excellent results Staining Finish is generally satisfactory Good staining properties Finish is generally good Strength Properties Bending strength (MOR) = high Max. crushing strength = high Hardness (side grain) = medium Modulus of Elasticity (stiffness) = high Density (dry weight) = 46-52 lbs/cu. ft. Shearing strength (parallel to grain) = medium Shrinkage, Tangential = fairly large Shrinkage, Volumetric = moderate Shrinkage, Radial = moderate Shrinkage, Radial = fairly large Max. crushing strength = medium Bending strength (MOR) = medium Toughness-Hammer drop (Impact Strength) = medium Shrinkage, Volumetric = fairly large Shrinkage, Tangential = small Shrinkage, Tangential = large Shrinkage, Radial = small Modulus of Elasticity (stiffness) = mediun Hardness (side grain) = soft Toughness-Hammer drop (Impact Strength) = low Shrinkage, Radial = large Modulus of Elasticity (stiffness) = low Density (dry weight) = 38-45 lbs/cu. ft. Toughness-Hammer drop (Impact Strength) = high Shrinkage, Volumetric = large Shrinkage, Tangential = moderate Shrinkage, Radial = very small Density (dry weight) = 31-37 lbs/cu. ft. Crushing strength = high Bending strength (MOR) = low Strength properties are somewhat higher than those of European beech (Fagus ) Numerical Data Item Green Dry English Bending Strength 12349 18428 psi Density 46 lbs/ft3 Hardness 1534 lbs Impact Strength 38 inches Maximum Crushing Strength 6198 8754 psi Shearing Strength 2205 psi Stiffness 1984 2208 1000 psi Specific Gravity 0.59 Weight 44 35 lbs/ft3 Radial Shrinkage 4 % Tangential Shrinkage 8 % Volumetric Shrinkage 12 % Item Green Dry Metric Bending Strength 868 1295 kg/cm2 Density 737 kg/m3 Hardness 695 kg Impact Strength 96 cm Maximum Crushing Strength 435 615 kg/cm2 Shearing Strength 155 kg/cm2 Stiffness 139 155 1000 kg/cm2 Specific Gravity 0.59 Weight 705 560 kg/m3 Radial Shrinkage 4 % Tangential Shrinkage 8 % References Bolza, E., Keating, W.G.,1972,African Timbers - the Properties, Uses and Characteristics of 700 Species,C.S.I.R.O. Div. of Building Research Boone, R.S., C.J. Kozlik, P.J. Bois and E.M. Wengert. 1988. Dry Kiln Schedules for Commercial Woods: Temperate and Tropical. United States Department of Agriculture, Forest Service, General Technical Report FPL-GTR-57, Forest Products Laboratory, Madison, Wisconsin. Chudnoff, M.,1984,Tropical Timbers of the World,U.S.A. Department of Agriculture, Forest Service, Forest Products,Laboratory, Madison. Cox, H.A.,1940,Notes on Empire Timbers,Empire Forestry Journal,19(2, pp242-4 Eggeling, W.J.,1940,Indigenous Trees of Uganda,Govt. Printer Entebbe Uganda Erfurth, T., Rusche, H.,1976,The Marketing of Tropical Wood A. Wood Species from African Moist Forests,F.A.O. Forestry Department Farmer, R.H.,1972,Handbook of Hardwoods,HMSO Forest Products Research Laboratory, U.K.,1950,The Seasoning Properties of Exotic Timbers,Forest Products Research Laboratory, Princes Risborough, Department of,Science and Industrial Research Leaflet,No.44 and supplements 1 & 2 Forests Products Research Laboratory, U.K.,1956,A Handbook of Hardwoods,Forest Products Research Laboratory, Princes Risborough, Department of,Science and Industrial Research, Building Research Establishment Fouarge, J.,1970,Essais Physiques,Mecaniques et de Durabilite de Bois de la Republique,Democratique du Congo,I.N.E.A.C. Belgium Serie Technique,No.76 France - C.T.F.T./C.T.B.,1982,Guide pour le Choix des Essences Deroulables-pour la fabrication du,contreplaque,C.T.F.T./C.T.B. France France - C.T.F.T.,Promotion of Ivory Coast Timbers. New Series (Leaflets,C.T.F.T. Ghana - Timber Marketing Board,1969,Ghana Hardwoods,Timber Marketing Board HMSO. 1981. Handbook of Hardwoods, 2nd Edition. Revised by R.H. Farmer. Department of the Environment, Building Research Establishment, Princes Risborough Laboratory, Princes Risborough, Aylesbury, Buckinghamshire. Hughes, J.F.,1971,The Principal Timber Trees of Cameroon,Unpublished data Irvine, F.R.,1961,Woody Plants of Ghana,O.U.P. London Istas, J.R., et al,1959,Etude de quelques Bois Congolais,I.N.E.A.C. Belgium Serie Tec., No.59 ITTO. 1986. Tropical Timber Atlas, Volume 1 - Africa. International Tropical Timber Organization (ITTO) and Centre Technique Forestier Tropical (CTFT, 45bis, Avenue de la Belle Gabrielle, Nogent-sur-Marne Cedex, France. ITTO. New Marketable Species in Africa - Celtis. Technical Notes. Prepared by Centre Technique Forestier Tropical (CTFT, Division of CIRAD, 45 bis, Avenue de la Belle Gabrielle, 94736 Nogent-sur-marne Cedex, France. Jay, B.A.,1968,Timbers of West Africa,TRADA, Red Booklet Series Keay, R.W.J. 1989. Trees of Nigeria. Revised Version of Nigerian Trees. Clarendon Press, Oxford. Keay, R.W.J.,1964,Nigerian Trees Vol.2,Nigeria Federal Department of Forest Research, Ibadan Kennedy, J.D.,1936,Forest Flora of Southern Nigeria,Government Printer Lagos Kinloch, D., Miller, W.A.,1949,Gold Coast Timbers,Govt. Printer Gold Coast Kloot, N.H., Bolza, E.,1961,Properties of Timbers Imported into Australia,C.S.I.R.O. Forest Products Division Technological Paper,No.12 Lebacq, L., Dechamps, R.,1967,Contribution a un Inventaire de Forets du Nord-kasai,Musee Royal de L'Afrique Centrale Belgium Annals Series 8 No.5 Palmer, E. and N. Pitman. 1972. Trees of Southern Africa, Volume 1 - Covering All Known Indidenous Species in the Republic of South Africa, South-West Africa, Botswana, Lesotho & Swaziland. A.A. Balkema, Publisher. Cape Town, South Africa. Patterson, D.N.,1963,The strength of Kenya timbers, their derivation and application,Kenya Forestry Department Research Bulletin,No.23 Pieters, A.,1977,Essences Forestieres du Zaire,R.U.G. Gent Belguim Sallenave, P.,1955,Proprietes Phyiques et Mecaniques des Bois Tropicaux de l'Union Francaise,C.T.F.T Sallenave, P.,1964,Proprietes Physiques et Mecaniques des Bois Tropicaux (Premier Supplement,C.T.F.T. Publ.,no.23 Scott, M.H.,1950,Notes on the more Important African Timbers Imported into the Union with,Special Ref. to Port. E.A. Species,Journal of the South African Forestry Association,No.19,pp18-62,[South,African Forestry Journal] Spalt, H.A., Stern, W.L.,1956,Survey of Africa Woods 2,Tropical Woods 16(106) pp65-97 Spalt, H.A., Stern, W.L.,1956,Survey of African woods 1,Tropical Woods,115(105,pp 13-38 Tack, C.H.,1969,Uganda Timbers,Govt. Printer Uganda Tanzania Forest Department,1961,Timbers of Tanganyika - Brachystegia spiciformis,Tanzania Forest Dept. Util. Sec. Moshi - Timbers of Tanganyika Taylor, C.J.,1960,Synecology and Silviculture in Ghana,University College of Ghana Thomas Nelson and Sons Timber Development Association Ltd.,1955,World Timbers (3 Vols.,Timber Development Association Ltd. Timber Information Assoc. Ltd.,1947,Notes on East African Timbers,TRADA, Timber Information, No.28 Titmuss, F.H.,1965,Commercial Timbers of the World,Technical Press Ltd., London, 3rd edition Uganda Forest Department,1954,Celtis - Celtis soyauxii,Uganda Forestry Department Timber Leaflet,No.15 Uganda Forest Department,1954,Flooring Timbers,Uganda Forest Department Timber Leaflet,No.17 Uganda Forest Department,1954,The Mechanical Properties of some Ugandan Timbers,Uganda Forest Department Timber Leaflet,No.1 WCMC. 1992. Conservation Status Listing: Trees and Timbers of the World. World Conservation Monitoring Center (WCMC, Plants Program, 219 Huntingdon Road, Cambridge, CB3 ODL, United Kingdom. Wimbush, S.H.,1950,Catalogue of Kenya Timbers,Govt. Printer Nairobi Kenya