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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 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 Luster Mortising Moulding Movement in Service Nailing Natural Durability Natural Growth Defects Numerical Data Odor Painting Planing Polishing Product Sources References Regions of Distribution Resin Content Resistance to Impregnation Response to Hand Tools Sanding Sapwood Color Scientific Name Screwing Strength Properties Synonyms Texture Toxicity Trade Name Tree Identification Tree Size Turning Veneering Qualities Scientific Name Mammea africana Trade Name Oboto Family Name Guttiferae Synonyms Garcinia golaensis, Mammea ebboro Common Names Aborzok, Aborzole, Abotoasebie, Abotzok, Abrompesowa, African apple, African apricot, African mammea apple, African mammy apple, Apegya, Bastard mahogany, Bjimbo, Bletui, Bletune, Bokoli, Boliki, Bompegya, Boza, Djimbo, Duforokoto, Ebornzork, Ibeka, Ibelea, Kaikumba, Libu, M'bossi, M'boza, Mammea, Muboro, Oboto, Oligbomidu, Ologbomodu, Ooboto, Pasin, Passee, Pegya, Tshilungu Regions of Distribution Africa Countries of Distribution  [VIEW MAP] Angola, Cameroon, Central African Republic, Congo, Gabon, Ghana, Ivory Coast, Liberia, Madagascar, Nigeria, Sierra Leone, Uganda, Zaire Common Uses Barge fenders, Bent Parts, Boat building (general), Bridge construction, Building construction, Building materials, Cabin construction, Cabinetmaking, Chairs, Chests, Construction, Crossties, Decorative plywood, Desks, Dining-room furniture, Docks, Dockwork, Domestic flooring, Drawer sides, Excelsior, Factory construction, Fine furniture, Flooring, Furniture , Furniture components, Furniture squares or stock, Furniture, General carpentry, Harbor work, Hatracks, Heavy construction, Interior construction, Interior trim, Joinery, Kitchen cabinets, Light construction, Living-room suites, Marine construction, Millwork, Mine timbers, Naval architecture, Office furniture, Parquet flooring, Piling, Plywood, Posts, Railroad ties, Turnery, Vehicle parts, Veneer: decorative Environmental Profile Generally secure within most of its natural habitat, but note exceptions. Data source is World Conservation Monitoring Center In Uganda it is Rare and it is Vulnerable in Cameroon and the Ivory Coast Distribution Overview Found in mixed deciduous forests from Sierra Leone to Angola and Zaire, prefers rather wet environment and sometimes forms small stands on flood plains. Heartwood Color Red Purple Brown Green/grey Reddish brown Dark brown Red Purple Flecked with gum ducts Darkens with age Sapwood Color Red Well defined Pinkish Different than heartwood Paler than heartwood Light brown to pink brown Grain Straight Interlocked Even Straight Interlocked Tangential surfaces show black speckles Straight to interlocked Radial surfaces show ribbon figure Longitudinal surfaces are yellow-tinted, with gum-filled vessels The wood will occasionally show black speckles on tangential surfaces. Texture Fine Coarse Medium Fine Fine to medium Medium coarse to coarse Coarser than is found in true mahoganies Luster Dull Slightly lustrous Lustrous Lacks luster of mahogany Natural Growth Defects Latex or other ducts Gum and mineral deposits Natural Durability Durable Very durable Resistant to powder post beetles Susceptible to insect attack Resistant to termites Resistant to marine borers Resistant to attack from powder post (Lyctid & Bostrychid) beetles Moderately resistant to termite (Isoptera) attack Moderately durable Durable Susceptible to attack from termites (Isoptera) Resistant to attack from termites (Isoptera) Heartwood resistant to decay Heartwood is moderately susceptible to termites Odor No specific smell or taste Resin Content Contains yellow resin in vessels on longitudinal surfaces Toxicity Dermatitic effects Kiln Schedules Dry at a slow speed Drying Defects Checking Moderate collapse and honeycombing Moderate twist/warp Moderate end spitting Collapse and honeycombing are often severe Ease of Drying Slowly Difficult Difficult to dry because of high moisture content Controlled drying conditions will prevent rapid drying and yield best results. Kiln Drying Rate Naturally dries slowly Tree Identification Bole/stem form is straight Bole/stem form is not buttressed Bole/stem form is cylindrical Bole/stem form is fluted Bole/stem form is buttressed Tree Size Tree height is 20-30 m Tree height is 10-20 m The trees are often swollen at the base and are somewhat lobed Product Sources Compared to some of the popular imports, supplies are rather limited through normal retail channels, but available quantities are more than adequate. Price is in the moderate range. Comments General finishing qualities are rated as satisfactory Blunting Effect Blunting effect on machining is moderate Medium effect due to high mineral content Blunting effect on machining is fairly severe Cutting Resistance Fairly Difficult to Very Difficult to saw Cutting Resistance with green wood is easy Cutting Resistance with dry wood is easy Cleanly but slowly The wood saws cleanly but slowly. High gum content tends to clog up saws. Gluing Easy to glue Mortising Easy to mortise Finishes well Moulding Easy to mould Movement in Service Not stable/prone to move Medium to high Nailing Fairly Difficult to Very Difficult Easy to nail Possible if prebored Holds nails well Planing Easy to plane Satisfactory planing properties Resistance to Impregnation Permeable sapwood Resistant heartwood Resistant sapwood Heartwood is resistant Resistant Heartwood is extremely resistant Response to Hand Tools Fairly Difficult to Difficult to Work Easy to machine Sanding High gum content may clog sandpaper Screwing Possible if prebored Easy to screw Screwing yields good results Turning Fairly Easy to Very Easy Good results Cutting edges tend to dull rapidly due to high gum and mineral content Veneering Qualities Exudes large amounts of gum if veneer is hot-pressed into plywood Diifficult to veneer Painting Poor results Difficult to paint Polishing Very Good to Excellent Results Fair to Good Results Satisfactory results Good results Poor results Excellent results Strength Properties Max. crushing strength = high Bending strength (MOR) = high Shrinkage, Radial = large Shrinkage, Tangential = large Density (dry weight) = 46-52 lbs/cu. ft. Modulus of Elasticity (stiffness) = medium Hardness (side grain) = medium Bending strength (MOR) = medium Shrinkage, Tangential = fairly large Shearing strength (parallel to grain) = medium Density (dry weight) = 53-60 lbs/cu. ft. Density (dry weight) = 38-45 lbs/cu. ft. Bending strength (MOR) = very high Weight = very high Shrinkage, Radial = fairly large Shearing strength (parallele to grain) = very high Shearing strength (parallel to grain) = high Resists denting and marring Modulus of Elasticity (stiffness) = low Max. crushing strength = medium Hardness = medium Hardness (side grain) = very hard Hardness (side grain) = hard Density = high Compression strength (parallel to grain) = very high Numerical Data Item Green Dry English Bending Strength 13131 17100 psi Crushing Strength 1362 psi Density 48 lbs/ft3 Hardness 1707 lbs Maximum Crushing Strength 6628 9259 psi Shearing Strength 2241 psi Static Bending 9898 psi Stiffness 1614 1861 1000 psi Toughness 171 inch-lbs Specific Gravity 0.58 0.69 Weight 46 37 lbs/ft3 Radial Shrinkage 6 % Tangential Shrinkage 9 % Volumetric Shrinkage 14 % Item Green Dry Metric Bending Strength 923 1202 kg/cm2 Crushing Strength 95 kg/cm2 Density 769 kg/m3 Hardness 774 kg Maximum Crushing Strength 466 650 kg/cm2 Shearing Strength 157 kg/cm2 Static Bending 695 kg/cm2 Stiffness 113 130 1000 kg/cm2 Toughness 196 cm-kg Specific Gravity 0.58 0.69 Weight 737 592 kg/m3 Radial Shrinkage 6 % Tangential Shrinkage 9 % References Arno, J. 1989. Mammea africana - Oboto. In A Guide to Useful Woods of the World. Flynn Jr., J.H., Editor. King Philip Publishing Co., Portland, Maine. 1994. 224-225. Banks, C.H. and J.P. Schoeman. 1963. Railway Sleeper and Crossing Timbers. Bulletin No. 41, Republic of South Africa. The Government Printer, Pretoria, South Africa. Banks, C.H., Schoeman, J.P., Otto, K.P.,1977,The Mechanical Properties of Timbers with particular reference to South,Africa,South African Forestry Research Institute Bulletin,(Ed.,Schoeman, J.P. 1973 & Otto K.P. 1976,No.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 Chalk, L.,1933,Twenty West African Timber Trees,Forest Trees and Timbers of the British Empire,Part 2 Chudnoff, M.,1984,Tropical Timbers of the World,U.S.A. Department of Agriculture, Forest Service, Forest Products,Laboratory, Madison. Erfurth, T., Rusche, H.,1976,The Marketing of Tropical Wood A. Wood Species from African Moist Forests,F.A.O. Forestry Department Ferreirinha, M.P.,1962,Madeiras de Angola - 2nd Series,Garcia de orta Lisbon,10 (1) Fouarge, J.,1950,Appropriation de Bois Congolais aux Besoins de la Metropole,I.N.E.A.C. Belgium Serie Technique,No.38 Fouarge, J.,1953,Bois du Congo,I.N.E.A.C. France - C.T.F.T.,1961,Resultats des Observations et des essais Effectues au C.T.F.T sur Oboto,C.T.F.T. Information Technique,No.103 Ghana - Timber Marketing Board,1969,Ghana Hardwoods,Timber Marketing Board Hughes, J.F.,1971,The Principal Timber Trees of Cameroon,Unpublished data 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 Jay, B.A.,1968,Timbers of West Africa,TRADA, Red Booklet Series Kinloch, D., Miller, W.A.,1949,Gold Coast Timbers,Govt. Printer Gold Coast Kryn, J.M., Forbes, E.W.,1959,The Woods of Liberia,U.S.A. Department of Agriculture,Forest Products Laboratory, Madison,,Report No. 2159 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 Man Mohan Singh, et al.,1977,A reappraisal of the suitability of Melia azedarach as a paper making new,material,Indian Forester 103(9) pp641-50 Organisation for European Economic Co-operation,1951,African Tropical Timber (Nomenclature, Description,OEEC 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 Stevens, W C,1961,Kiln Operators Handbook,HMSO Takahashi, A.,1978,Compilation of Data on the Mechanical Properties of Foreign Woods (Part,III) Africa,Shimane University, Japan, Research Report on Foreign Wood No. 7 Unwin, A.H.,1920,West African Forests and Forestry,T. Fisher Unwin Ltd. London WCMC. 1992. Conservation Status Listing - Trees and Timbers of the World. World Conservation Monitoring Center-Plants Programme, Cambridge, CB3 ODL, United Kingdom. Wood, B., Calnan, D.,1976,Toxic Woods,British Journal of Dermat 94 Suppl. 13