Search for

Clicking any heading in the main data area (at right) will scroll the page back to this top position. Use the following links to jump to the associated section in the main data. Blunting Effect Boring Carving Comments 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 Light-Induced Color Change Mortising Moulding Movement in Service Nailing Natural Durability Natural Growth Defects 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 Staining Steam Bending Strength Properties Substitutes Synonyms Texture Trade Name Tree Identification Tree Size Turning Veneering Qualities Scientific Name Khaya grandifoliola Trade Name African mahogany Family Name Meliaceae Synonyms Khaya grandis, Khaya punchii Common Names Acajou, Acajou grandes feuilles, African mahogany, Akor, Akuk, Apenkwa, Appapayi, Asamogo, Bandoro, Benin mahogany, Big leaf mahogany, Bogu, Diala-iri, Digiten, Diki, Dirinshi, Dubini, Dukru, Dukuma, Dumanami, Eri, Eri kire, Eri kiree, Gadeau, Gagaliga, Heavy African mahogany, Homraya, Khaya mahogany, Kruba, Krubna, Loukrou, Male, Mario, Munyama, Murraya, Obon, Odala, Oduben, Odupon, Oganwo, Ogwango, Ono, Senegal mahogany, Tiama-tiama, Tido, Trio, Upono, Wansanwa, Wausauwah Regions of Distribution Africa Countries of Distribution  [VIEW MAP] Benin, Cameroon, Congo, Ghana, Guinea, Ivory Coast, Nigeria, Sudan, Tanzania, Togo, Uganda, Zaire Common Uses Balusters, Bedroom suites, Boat building (general), Boat building, Boat building: decking, Building construction, Building materials, Cabinetmaking, Canoes, Carvings, Construction, Decorative veneer, Domestic flooring, Drawer sides, Drum sticks, Excelsior, Factory flooring, Figured veneer, Flooring, Furniture , Furniture, Heavy construction, Interior construction, Interior trim, Joinery, Kitchen cabinets, Lifeboats, Light construction, Living-room suites, Millwork, Moldings, Musical instruments , Musical instruments, Novelties, Office furniture, Organ pipes, Paneling , Paneling, Parquet flooring, Piano keys, Pianos , Plywood, Pulp/Paper products, Pulpwood, Radio - stereo - TV cabinets, Shipbuilding, Sounding boards, Tables, Turnery, Veneer, Veneer: decorative Environmental Profile Secure in many areas of its range Data source is World Conservation Monitoring Center Vulnerable in Benin and Uganda Distribution Overview West tropical Africa from the Guinea Coast to Cameroon and extending eastward through the Congo basin to Uganda and parts of Sudan (Benin, Côte d'Ivoire, DR Congo, Ghana, Guinea, Nigeria, Sudan, Togo, Uganda).  Often found in the fringe between the rain forest and the savanna, in dry semi-deciduous forest or rocky forest and forest outliers. Heartwood Color Brown Red Pale red to pink Dark brown Reddish brown Brown Red Pink Pale brown Light brown Savanna-Grown timber is usually darker than forest-grown timber. Sapwood Color White Brown Pink Grey Paler than heartwood Pinkish Well defined Straw colored Color not distinct from heartwood 2 inches (5 cm) wide Grain Figure Interlocked Distinct (figure) Straight Even Growth rings (figure) Irregular Other (figure) Rippled (figure) Interlocked Distinct figure Straight Rippled figure Other figure Irregular Clear growth rings (figure) The grain is often irregular in direction and sometimes very wild. Texture Fine Even or uniform Medium coarse to coarse Coarse Medium Open Fine to medium Natural Growth Defects Logs may have brittleheart or softheart, and cross fractures or heartbreaks may also be present Natural Durability Durable Moderately durable Non-resistant to termites Susceptible to attack from powder post (Lyctid & Bostrychid) beetles Moderately durable Resistant to attack from termites (Isoptera) Durable Sapwood susceptible to attack by powder post beetles Resistant to attack from powder post (Lyctid & Bostrychid) beetles Pinworms (ambrosia beetles) often present in the standing tree Pinworms (ambrosia beetles) may be present in the felled log Non durable Heartwood resistant to decay Trees and logs are are also liable to attack by forest longhorn beetle. Odor No specific smell or taste Light-Induced Color Change Darker Kiln Schedules Drying (speed) is fast Kiln Drying Rate (in days) is rather slow Dry at a slow speed Dry at a moderate speed Drying Defects Ring Shakes Splitting Distortion Slight twist/warp Slight surface checking Warping can be expected Slight cupping No twisting or warping Moderate twist/warp Moderate end spitting Moderate cupping Cups Checks Trees containing softheart may exhibit uneven and excessive shrinkage and high distortion. Ease of Drying Slowly Easy Dries well Dries slowly with little degrade Radial - 2.5% Shrinkage from green to 12% MC Tangential - 4.5% Kiln Drying Rate Slow (18-28 days for boards < 32 mm, to 52-84 days for boards >= 63 mm) Tree Identification Bole/stem form is buttressed Bole/stem form is misshapen Tree Size Tree height is 30-40 m Khaya grandifoliola trees are smaller than those of K. ivorensis or K. anthotheca . The buttressed tree develops a bole that is often twisted. Product Sources The ITTO reports that the species is a regular source of timber for export. The species is often marketed with Khaya ivorensis , K. anthotheca , and K. senegalensis . Supplies are abundant in a wide range of sizes in the lumber form and at a moderate cost. It is also readily available in plywood form from many lumber suppliers. African mahogany is often used instead of American mahogany because it is more abundant and costs less. Substitutes Crabwood (Carapa guianensis) is similar in appearance and is nearly as tough. Sapele (Entandrophragma cylindricum) has superiod strength properties. African canarium (Canarium schweinfurthii) is extremely similar in appearance once it is stained. Comments General finishing qualities are rated as good Some strength properties of this species are significantly different from those of Khaya ivorensis and K. anthotheca . It is appreciably harder and stronger than K. ivorensis , and is similar to European beech (Fagus sylvatica ) in strength properties. Blunting Effect Moderate Moderate effect Blunting effect on machining is moderate Boring Fair to good results Fairly easy to very easy The timber bores to yield good results, except in material with wild grain Carving Fairly Easy to Very Easy Material containing wild grain is generally difficult to work to a smooth finish. Cutting Resistance Cutting Resistance with dry wood is easy Brown - medium value Gluing Fair to Good Results Fairly Easy to Very Easy Easy to glue Good properties Mortising Fair to Good Results Fairly Easy to Very Easy Straight-Grained material mortises easily, but wood with irregular grain may be difficult to work to a smooth finish Moulding Fairly Easy to Very Easy The wood moulds with good results except in material with wild grain, which may cause fuzzy surfaces Movement in Service Excellent Stability - Small Movement Small Nailing Fairly Difficult to Very Difficult Easy to nail Tends to split during nailing Planing Fair to Good Results Fairly Easy to Very Easy Easy to plane Timber produced by K. grandifoliola is more difficult to work than that by K. anthotheca . It generally planes well, but material with irregular grain is rather difficult to dress to a smooth finish. Resistance to Impregnation Resistant sapwood Resistant heartwood Heartwood is highly resistant Sapwood is moderately resistant Response to Hand Tools Easy to machine Moderate working qualities Gives good results with all hand tools Routing & Recessing Fairly Easy to Very Easy The timber works well with all hand and machine tools to produce good results Sanding Responds well to sanding operations Easy to sand Screwing Very good screwing qualities Turning Fairly Easy to Very Easy Easy to turn The wood is reported to turn well although smooth surfaces may be difficult to achieve in material containing wild grain. Veneering Qualities No drying degrade. Dries flat without splitting Diifficult to veneer Less suitable for conversion into plywood than other Khaya species because of its weight and irregular grain. Steam Bending Very poor Very poor steam bending properties because of excessive cross grain. Polishing Fair to Good Results Fairly Easy to Very Easy Satisfactory results Good results Staining Fair to Good Results Fairly Easy to Very Easy Strength Properties Density (dry weight) = 46-52 lbs/cu. ft. Density (dry weight) = 38-45 lbs/cu. ft. Bending strength (MOR) = medium Max. crushing strength = high Hardness (side grain) = medium Shrinkage, Tangential = small Shrinkage, Radial = small Modulus of Elasticity (stiffness) = low Max. crushing strength = medium Hardness (side grain) = soft Shrinkage, Tangential = moderate Shrinkage, Radial = moderate Bending strength (MOR) = high Shrinkage, Volumetric = small Shrinkage, Volumetric = moderate Shrinkage, Tangential = very small Shrinkage, Radial = very small Shearing strength (parallel to grain) = medium Shearing strength (parallel to grain) = low Modulus of Elasticity (stiffness) = very low Density (dry weight) = 31-37 lbs/cu. ft. Toughness-Hammer drop (Impact Strength) = low Shrinkage, Tangential = fairly large Shearing strength (parallel to grain) = high Bending strength (MOR) = very high Bending strength (MOR) = low Numerical Data Item Green Dry English Bending Strength 10332 15263 psi Density 44 lbs/ft3 Hardness 1395 lbs Impact Strength 28 27 inches Maximum Crushing Strength 5462 8255 psi Shearing Strength 2163 psi Stiffness 1349 1570 1000 psi Work to Maximum Load 10 12 inch-lbs/in3 Specific Gravity 0.39 0.53 Weight 41 41 lbs/ft3 Radial Shrinkage 3 % Tangential Shrinkage 6 % Volumetric Shrinkage 10 % Item Green Dry Metric Bending Strength 726 1073 kg/cm2 Density 705 kg/m3 Hardness 632 kg Impact Strength 71 68 cm Maximum Crushing Strength 384 580 kg/cm2 Shearing Strength 152 kg/cm2 Stiffness 94 110 1000 kg/cm2 Work to Maximum Load 0.70 0.84 cm-kg/cm3 Specific Gravity 0.39 0.53 Weight 657 657 kg/m3 Radial Shrinkage 3 % Tangential Shrinkage 6 % References Bois et Forets des Tropiques,1979,Acajou D'Afrique (Khaya spp.,Bois et Forets des Tropiques,183,pp33-48 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, E.M. Wengert. 1988. Dry Kiln Schedules for Commercial Hardwoods - Temperate and Tropical. USDA, 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. Eggeling, W.J., Harris, C.M.,1939,Fifteen Uganda Timbers,Forest Trees and Timbers of the British Empire, Imperial Forestry,Institute, Oxford,Part 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.,1969,The Movement of Timbers,Forest Products Research Laboratory, Princes Risborough Technical Note,No.38 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 France - C.T.F.T.,Resultats des Observations et des Essais Effectues au CTFT sur Khaya,grandifolia,C.T.F.T Information Technique France - Comite Nacional des Bois Coloniaux,1931,Etude Physique et Mecanique des Bois Coloniaux,Assoc. Colonies-Sciences & Comite National des Bios Coloniaux, Paris,,France Greenway, P.J.,1947,Mahogany in East Africa 1 The Khayas,East African Agricultural Journal,13,pp8-14,[East African Agricultural,and Forestry Journal] 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. I.U.F.R.O.,1973,Veneer Species of the World,Assembled at F.P.L. Madison on behalf of I.U.F.R.O. Working Party on,Slicing and Veneer Cutting Irvine, F.R.,1961,Woody Plants of Ghana,O.U.P. London ITTO. 1986. Tropical Timber Atlas, Volume 1- Africa. International Tropical Timber Organization (ITTO) and Centre Technique Forestier Tropical (CTFT, 45bis, Avenu