Wood properties database

EXPLANATORY NOTES AND ENTRY CODES FOR WOOD PROPERTIES DATABASE

1. NOMENCLATURE 1.1 Botanical/Scientific name

1.3 Family

The timber species ate presented individually according to their botanical names. Botanical names consist of a combination of a genus and a species name. Author citations are included for completeness. Example: Ocotea bullata (Burch.) E. Mey. Botanical names are standardized according to Index Kewensis – an enumeration of the genera and species of flowering plants. Supplement 1 - 16, published by the Royal Botanic Gardens, Kew, England. After 1985 the name of this publication changed to Kew Index, of which yearly publications are available for 1986 – 1989. Other publications that were consulted, are: Bailey H.B. & Bailey E.Z. 1978. Hortus Third – a concise dictionary of plants cultivated in the United States and Canada. Macmillan Publising Co., New York. Von Breitenbach F. 1990. National List of Indigenous Trees. Dendrological Foundation, Pretoria. Von Breitenbach F. 1989. National List of Introduced Trees. Dendrological Foundtation, Pretoria.
1.2 Synonyms

Families, to which the species belong, are included. Plants developing woody tissues are classified in about 250 families, of which eight belong to the Gymnospermae (softwoods/conifers) and the rest to the Angiospermae (hardwood/broad-leaved species).
1.4 Hardwood/Softwood

The classification in this field will indicate whether the species is a hardwood (broadleaved) species) or a softwood (conifer).
1.5 Trade name(s)

These are the names most commonly used in the local and international timber trade. Trade names are standardized in the literature. No single publication can be referred to her. The single most commonly used trade name is captured in this field to facilitate quick searches. Preferences is give to the English or most common trade name. The Afrikaans trade name (where available) is listed in the field for vernacular names.
1.6 Vernacular and common names

These include all names available from the literature to our disposal. Vernacular names are followed by the name of a country or ethnic group (where available). Common names were obtained from the available literature and a card system which has been kept up to date by researchers at the S.A. Forestry Research Institute through the years. (This system is often consulted to search for the botanical name when only a common name is available).
1.7 Distribution

A synonym is an earlier “valid” name that has been superseded by another name. Name changes may occur more than once and it is important to list all existing synonyms for each species. Synonyms are standardized according to the publications listed in 1.

In this field the countries are listed in which the species occurs naturally. This field does not list information on areas where the species is planted outside its natural habitat. Distribution data is obtained from the available literature.

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2. WOOD PROPERTIES 2.1 Heartwood colour

2.4 Sapwood differentiation from heartwood

Heartwood is the term for the inner layers of wood which, in the growing tree contain cells which are physiologically inactive and in which reserve materials (eg starch) have been removed or converted to more durable substances. It is generally darker in colour than the sapwood as a result of storing extractives, gums, resins, etc. Heartwood colour normally recorded, is that of a freshly cut longitudinal surface of sound wood. The colour of wood is not easily described because of the large variation that exists in the heartwood colour of many species. The following classes have been selected for this data base (preceded by the code selected for the property):
• • • • • • • •

The sapwood and heartwood are not always differentiated by colour. If this is the case, it should be recorded. The codes for the selection are Yes or No.
2.5 Texture

Texture refers to the structural character of wood as revealed by touch or reaction to cutting tools. It is determined by the distribution and size of the various woody elements and tissues. The following texture classes are recognized. • Coarse texture – relatively large elements or growth rings that are wide apart for the species concerned, give coarse texture. Fine texture – relatively small elements or narrow growth rings give fine texture. Uneven texture – caused by considerable variation in the element size or a distinct contrast between early wood and latewood within single growth rings. Even texture p very little variation in element size and no distinct contrast between early- and latewood zones. Combinations of these texture patterns are also included.

• •

White or whitish Yellow Yellow-brown to dark brown Pinkish or reddish Reddish-brown Black Green Grey

• •

In cases where the large variation in heartwood colour is not described sufficiently by these codes, a description of the colour is given in the field “OTHER”.
2.2 Sapwood colour

2.6 Grain pattern

Grain refers to the general direction or arrangement of the wood elements. The different classes are: • • • • Interlocked grain – an arrangement of wood elements in which the inclination of the grain reverses. Silver grain – figure produced on quarter-sawn timber by conspicuous rays, as in oak. Spiral grain – an arrangement of the woody elements in which they follow a spiral course round the stem. Straight grain – an arrangement of the wood elements generally parallel to the axis of the tree. Wavy grain – the arrangement of the elements in short, fairly uniform waves of ripples.

Sapwood refers to the outer layers of wood which, in the growing tree contain living cells and reserve material. It is generally lighter in colour than the heartwood. The classes for this field are:
• • •

White Yellow Grey will be

Any other sapwood colour described in the field “OTHER”.
2.3 Sapwood width

•

The range for sapwood width (the distance between the heartwood and bark of a tree or log) is given in mm.

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2.7 Lustre

Certain woods produce a high luster or golden cast due to the way light is reflected. The options for this field are Yes or No.
2.8 Characteristic odour

• • •

Small Medium Large

- Under 3.0 percent - 3.0 to 4.5 percent - Over 4.5 percent

3.4 Density

This refers to wood which has been seasoned and not to green, partly seasoned timber, which often has a pronounced natural odour and sometimes a rancid smell resulting from fermentation. The odour of dry wood can be enhanced by breathing on or slightly warming and moistening the surface. The codes for odour are Yes or No.
2.9 Irritant properties

The weight of a piece of wood clearly varies with the amount of water that it contains. It is therefore important that, when the weight, or more strictly, the density of a timber is quoted, the moisture content at which the weight was recorded, is stated. In the database the average air dry density and the density range at 12% moisture content will be recorded. This information is taken from published literature.
4. MECHANICAL STREGTH PROPERTIES

Some woods have constituents that are allergenic or toxic to humans. Dust generated in woodworking may irritate skin and mucous membranes and even cause nosebleeds and respiratory disorders. The irritant properties are described briefly in the data base.
2.10 Other

Any notes or special interest that are not covered by the other fields of the database, are recorded here.
3. DRYING AND SHRINKAGE 3.1 Drying properties

timber, like all other materials of construction, has the ability to resist applied or external forces. This resistance involves a number of specific mechanical properties, and it is mainly these that determine the suitability of different timber species for the various purposes for which they are used. It is therefore essential to have a basic knowledge of the strength properties of a timber to be able to use it efficiently. Average values are given for bending strength (MOR), stiffness (MOE), compression parallel to the grain (maximum compression strength) and impact bending (resistance to suddenly applied loads). Although the test conditions to obtain these values differ slightly at different timber research institutes, the results are comparable. The conditions used at the S.A. Foretsry Research Institute, Pretoria, are given in most cases. The values given apply only to the size of specimen and the loading conditions employed in the testing of clear specimens which are 51 mm square in cross section and 762 mm long. The results of these tests were published as a Departmental Bulletin:

Information is given on the response of individual woods to air-drying and kilndrying and whether or not there is a degrade due to checking, warp or collapse.
3.2 Shrinkage

Shrinkage values (%) (radial and tangential) from the green to oven-dry condition or green to air-dry condition are given.
3.3 Movement in use

Movement is the sum of radial and tangential movements of a timber from 90 per cent to 60 per cent relative humidity at 25 degrees Celsius and is represented as follows:

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Otto K.P. & Van Vuuren E.F.J. 1977. The mechanical properties of timbers, with particular reference to those grown in the Republic of South Africa. Bulletin 48, Department of Forestry, Pretoria. This publication will be used as a standard regarding mechanical properties. Where other publication were consulted, these will be listed in the field REFERENCES.
4.1 Modulus of Rupture (MOR)

sample, which is 279 mm long by 20 mm square in cross section. One half of the specimens are tested on the radial face and these are averaged to give the mean toughness value. Toughness is important when considering suitable timbers for articles such as sports equipment and handles for striking tools. Values are given in Joules (Nm).
5. DURABILITY AND PRESERVATION 5.1 Durability

This property is a measure of the ultimate bending strength of timber. The load is applied to the heart-side tangential face of the specimen at a constant rate of descent of 2.54 mm per minute. Values are given in MPa.
4.2 Modulus of Elasticity (MOE)

This property is of importance in determining the deflection of a beam under load – the greater the stiffness, the less the deflection. It is usually considered in conjunction with bending strength, as for many uses stiffness is the controlling factor in the design. MOE is used in calculating the deflection of beams, joists, purlins and stringers and in computing working stresses for long and intermediate columns. Values are given in MPa.
4.3 Compression parallel to grain

Resistance of the woof to attach by decay fungi, insects and marine borers is described here. Ratings are based on laboratory tests, field stake tests of performance under actual conditions of use. Heartwood durability classifications are based on ground contact and are:
Classification • • • • • Very durable Durable Moderately durable Non-durable Perishable Approximate service life more than 25 years 15 – 25 years 5 – 10 years 10 – 15 years less than 5 years

This property (maximum compression strength) measures the ability of a timber to withstand loads when applied on the end grain. This is of importance when short columns or props are contemplated. For this test specimens of 203 mm long and 51 mm square in cross section are used. The specimen is supported in the machine by a spherical-seated self-aligning block to ensure uniform distribution of the load. Loading of the specimen takes place at a rate of head descent of 0.61 mm per minute. Values are given in MPa.
4.4 Impact bending

Sapwood of all species will rate perishable. If not in ground contact and kept dry, all woods could be free of rot and have an extended service life. Consideration must also be given to vulnerability to attack by Lyctus beetles, subterranean and dry-wood termites.
5.2 Preservation

Treatability of sapwood and heartwood using either open tank or pressure-vacuum processes is described in this field. Ratings are based on laboratory trials using a wide range of specimen sizes. The codes used are as follows: • Permeable – Timbers that can be penetrated completely under pressure without difficulty, and can usually be heavily impregnated by the hot and cold open tank process.

This is a measure of the toughness of timber. It refers to the ability of wood to absorb a relatively large amount of energy, or to endure a repetition of shocks which exceed the proportional limit. The results of this test are obtained by applying an impact load at the middle of the span of a

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•

Moderately resistant – Timbers that are fairly easy to treat, and it is usually possible to obtain a lateral penetration of 6 – 18 mm in about 2 – 3 hours under pressure, or the penetration of a large proportion of the vessels. Resistant – Timbers that are difficult to impregnate under pressure and require a long period of treatment. It is difficult to penetrate them laterally more than 36 mm. Extremely resistant – These timbers absorb only a small amount of preservative, even under long pressure treatments. They cannot be penetrated to an appreciable depth laterally and only to a very small extent longitudinally.

The blunting effect on tools can be classified as: • • • • • Slight Moderate Severe Slight to moderate Moderate to severe

•

6.3 Planning

•

The two most important factors in planning are feed speed and cutting angle. Feed speed is independent of the species and is chosen in relation to the number of cutters and the rotational speed of the block, so that the pitch of the cutter marks on the planed surface is suitable for the end use of the timber. Cutting angle is determined by the species being planed. Three angles are used: 30º, 20º and 15º. The largest angle is suitable for most species, but when interlocked grain is present a reduced angle of 20º or even 15º may be necessary to avoid picking up of the surface. Some low density timbers give a woolly surface when planed with the normal 30º cutting angle. This will be noted against relevant species. This could be minimized by ensuring that cutting edges are maintained in a sharp condition.
6.4 Turning

6. WOODWORKING PROPERTIES

data on woodworking properties are based on tests carried out at the S.A. Forestry Research Institute, the National Timber Research Institute, CSIR, and other published information. Tests are normally carried out on material kiln dried or air dried to between 10 and 14 percent moisture content. All tests are carried out on commercial machines, maintained free from excessive wear and using standard tools operating at the settings and speeds recommended by the machine manufacturer. The standard test procedure includes an examination of the following factors:
6.1 Sawing

The suitability of a species for the manufacture of turned articles will be coded for with Yes or No.
6.5 Peeling and slicing

A short summary of the results of tests will be given as well as any specific recommendations for or problems with sawing of the species.
6.2 Blunting effect on tools

The rate of wear is a function of timber density and in some species is affected by the presence of silica or other abrasive substances. The literature suggests that little blunting of cutting tools occurs unless silica accumulations are above 0.5 percent.

Figured veneers for decorative purposes are usually cut from selected flitches in a slicer, a process that is feasible with almost all species. For plywood, however, veneer must be produced by rotary cutting in a lathe. Plywood is made for purposes ranging from the technical to the aesthetic. For the former, strength and durability are more important than appearance. For the latter, veneers of high quality and uniformity of colour are used for faces, others are used for core veneers. Technically, here are few timbers which, because of weight alone are unsuitable for plywood, but in practice, those outside the

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range 400-700 employed.

kg/m3

are

seldom

to the cross-cut end and beyond the nail in the opposite direction, it is noted.
6.7 Gluing

Two ratings will be used in this field, a classification for ease of cutting and an end use classification.
6.5.1 Peeling ease

Certain conditions are important when the gluing properties of a timber are determined: good gluing practice must be used, i.e. the wood must be at the correct moisture content the surface must be smooth and clean the glue must be spread to a uniform and adequate thickness the temperature and pressure have to be controlled

The three classifications are: •
• • Easy Moderate the wood is easy to cut into smooth, tight veneer of uniform thickness the wood is moderately easy to cut into smooth, tight veneer of uniform thickness the wood is difficult to cut into smooth, tight veneer of uniform thickness

Difficult -

When these conditions have been adhered to, the gluing characteristics of a timber can be stated as: • • • Good Variable Difficult

6.5.2 Recommended end use

The end use for veneer species are: Construction plywood, where the desirable qualities are high stiffness and strength, moderate weight and that the wood is readily glued. Decorative face veneer, the qualities being attractive figure and colour, moderately hard and readily glued. Inner plies for decorative panels, where the qualities are low weight, low shrinkage, straight grain, fine uniform grain and easily glued. Container veneer and plywood, the qualities being high in stiffness, shock resistance, resistance to splitting, light colour, free from odour and taste, moderate in weight.
6.6 Nailing

6.8 Bending

Classification of timbers according to their steam bending properties, is based mainly on the minimum bending radius of sound clear specimens, 25 mm thick, at a moisture content of 25 percent. The specimens are subjected to saturated steam for at least 45 minutes before bending. The following classification will be adopted: (The first column gives the radius of curvature at which breakages during bending should not exceed 5%. The second column gives the classification).
• • • • • less than 150 mm 150-250 mm 260-500 mm 510-750 mm exceeding 750 mm Very good Good Moderate Poor Very poor

A short description of the nailing properties is given. The nailing characteristics of a species are determined by hand driving 12 gauge wire nails into the face of 13 mm thick boards, 13 mm from the cross-cut end and from each edge. If the wood splits

6.9 Staining and polishing

Where available, the staining and polishing characteristics of species will be described briefly.

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7. USES 10. REFERENCES

For the field containing end uses, the list of 80 end uses of the Oxford Forestry Institute database and the card system used by FORESTEK have been combined. Presently 131 uses are listed. The lists of uses indicate the properties and working characteristics of the wood and may suggest applications still not realized. A standard list of 131 uses is used to select from for data capture. New uses are added as it becomes necessary.
8. SUBSTITUTE TIMBERS

1.

BAILEY H.B. & BAILEY E.Z.. 1978. Hortus Third – a concise dictionary of plants cultivated in the Unites States and Canada. Macmillan Publishing Co., New York. BERNI C.A., BOLZA E. & CHRISTENSEN F.J. 1979. South American timbers: The characteristics, properties and uses of 190 species. Commonwealth Scientific and Industrial Research Organisation (CSIRO), Division of Building Research, Melbourne, Australia. BOLZA E. & KEATING, W.G. 1972. African timbers: The properties, uses and characteristics of 700 species. Commonwealth Scientific and Industrial Research Organisation (CSIRO), Division of Building Research, Melbourne, Australia. BRAZIER J.D. & FRANKLIN G.L. 1961. Identification of hardwoods: A microscope key. Forest Products Research Bulletin 46. Department of Scientific and Industrial Research, HMSO, London. BUILDING RESEARCH ESTABLISHMENT. 1977. A handbook of softwoods. HMSO, London. CHUDNOFF M. 1984. Tropical timbers of the world. Agricultural Handbook 607. U.S. Department of Agriculture, Forest Service, Madison, Wisconsin. COATS PALGRAVE K. 1983. Trees of Southern Africa. Struik, Cape Town & Johannesburg. COETZEE S.T. 1983. Die houteienskappe van Suid-Afrikaansgekweekte Gmelina arborea Roxb. SA Bosboutydskrif125(1): 29-34.

2.

Numerous requests are received for substitute timbers for many of the wellknown, popular, imported timbers. Considerable research is necessary before accepting a substitute for the trade. Certain characteristics, such as colour, grain, texture, density, dimensional stability, mechanical and finishing properties, should be taken into consideration. Known substitutes will be listed here and data will be added as more information becomes available.
9. AVAILABILITY

3.

4.

5.

Information on the availability of timbers is difficult to supply and maintain. However, it would be considered at a later stage to do regular surveys of the supplies available at timber dealers and possibly secure an external income by designing a suppliers database which will be linked to the wood properties database. In the meantime this field will refer to the forest availability of the species and the classifications used are: • • • • Abundant Moderate availability Rare Very rare

6.

7.

8.

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9.

COETZEE S.T. & VAN VUUREN N.J.J. 1984. Characteristics and uses of South African timbers. Information leaflets, Department of Environment Affairs, Pretoria No. 12 Acacia nigrescens Oliv. No. 13 A. melanoxylon R. Br. No. 14 A. mearnsil De Wild. No. 15 Pterocarpus angolensis DC. No. 16 Breonadia microcephala (Del.) Ridsd. No. 17 Apodytes dimidiata E. Mey ex Arn. subsp. dimidiata.

16. HAUSEN B.M. Woods injurious to human health: a manual. De Gruyter, Berlin, New York. 17. INTERNATIONAL UNION OF FORESTRY RESEARCH ORGANISATIONS (IUFRO) Working party on slicing and veneer cutting. 1973. Veneer species of the world. Forest Products Laboratory, Forest Service, U.S. Department of Agriculture, Madison, Wisconsin, USA. 18. KRIBS D.A. 1968. Commercial foreign woods on the American Market. Dover publications, New York. 19. KROMHOUT C.P. 1967. Twintig Transvaalse houtsoorte. Fauna & flora 18: 3-30. 20. OTTO K.P. & VAN VUUREN W.F.J. 1976. The mechanical properties of timbers with particular reference to those grown in the Republic of South Africa. Bulletin 48. Department of Forestry, Pretoria. 21. PANSHIN A.J. & DE ZEEUW C. 1980. Textbook of wood technology. 4th ed. McGraw-Hill, New York. 22. POYNTON R.J. 1979. Tree planting in Southern Africa. Vol 1: The Pines. Vol 2: The Eucalypts. Department of Forestry, Pretoria. 23. ROYAL BOTANIC GARDENS 18951985. Index Kewensis – an enumeration of the genera and species of flowering plants. Supplement 1 – 16, Kew, England. 24. SCOTT, M.H. 1953. Utilisation notes on South African timbers. Bulletin 36. Department of Forestry, Pretoria. 25. SOUTH AFRICAN BUREAU OF STANDARDS 9SABS). 1960. Glossary of timber terms and definitions. SABS 065-1960, Pretoria. 26. TIMBER RESEARCH AND DEVELOPMENT ASSOSICAITON (TRADA). 1980. Timbers of the word. Vols. 1 & 2. Longman, New York.

10. DADSWELL H.E. & BURNELL M. 1932. Identification of the coloured woods of the genus Eucalyptus, Council for Scientific and Industrial Research, Bulletin 67, Melbourne, Australia. 11. DADSWELL H.E., BURNELL M. & ECKERSLEY A.M. 1934. Identification of the light-coloured woods of the genus Eucalyptus. Council of Scientific and Industrial Research, Bulletin 78, Melbourne, Australia. 12. DYER S.T. 1989. A description of the macroscopic characteristics of a number of well known indigenous and exotic timber species in South Africa and a key to their identification. Bulletin 62. South African Forestry Research Institute, Department of Environment Affairs, Pretoria. 13. FARMER R.H. 1975. Handbook of hardwoods. 2nd ed. Department of the Environment, Building Research Establishment, Princess Risborough Laboratory. HMSO, London. 14. FORD-ROBERTSON F.C. 1971. Terminology of forest science, technology, practice and products. Society of American Foresters, Washington, DC. 15. GOLDSMITH B. & CARTER D.T. 1981. Indigenous timbers of Zimbabwe. The Zimbabwe Bulletin of Forestry Research, No. 9. Forestry Commission, Salisbury.

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27. VAN DER WESTHUIZEN P.K. 1978. Hardwood import replacement and improved utilisation of locally grown hardwoods. CSIR Special Report. Hout 152, Pretoria. 28. VAN VUUREN N.J.J., BANKS C.H. & STöHR H.P. 1978. Shrinkage and density of timbers used in the Republic of South Africa. Bulletin 57. Department of Forestry, Pretoria. 29. VON BREITENBACH F. 1984. National List of Introduced Trees. Dendrological Foundation, Pretoria. 30. VON BREITENBACH F. 1990. National List of Indigenous Trees. Dendrological Foundation, Pretoria. 31. WAND E.K.R. 1990. Timbers of commercial value. Department of Wood Science. Universsity of Stellenbosch, Stellenbosch. 32. VON BREITENBACH F. 1965. The Indigenous Trees of Southern Africa. Vol. 1-5 Department of Forestry, Pretoria. 33. VAN WYK P. 1984. Veldgids tot die bome van die Nasionale Krugerwildtuin. Struik, Cape Town. 34. BOUTELJE J.B. 1980. Encyclopedia of world timbers – Names and technical literature. Swedish Forest Research laboratory, Stockholm. 35. EGGELING W.J. 1951. The indigenous trees of the Uganda Protectorate. Government Printer, Entebe, Uganda. 36. ASSOCIATION INTERNATIONALE TECHNIQUE DES BOIS TROPICAUX. 1986. Tropical timber atlas. Part and II. ATIBT, Paris. 37. PEARSON R.S. & BROWN H.P. 1932. commercial timbers of India. Vol. 1 and 11.Central Publication Branch, Government of India, Culcutta.

38. NATIONAL TIMBER RESEARCH INSTITUTE, CSIR. 1986. The 8 most important pine species in South Africa. Report X HOUT 1, CSIR, Pretoria. 39. GOMES E. & SOUSA A. 1948. Dendology of Mozambique. Mocambique No 64, 1951. 40. RECORD S.J. & HESS R.W. 1943. Timbers of the New World. Yale University Press, London. 41. STORRS A.E.G. 1979. “Know your trees” some of the common trees found in Zambia. The Forest Department, Ndola, Zambia. 42. FANSHAWE D.B. 1968. Fifty common trees of Zambia. Government Printer, Lusaka. 43. LINCOLN W.A. 1986. World woods in colour .Stobart & Son Ltd., London. 44. SWAIN E.H.F. 1928. The timbers and forest products of Queensland. Government Printer, Brisbane. 45. HIDAYAT S. & SIMPSON W.T. 1994. Theuse of greem ,oisture content and basic gravity to group tropical hardwoods for drying. Research Note FPL-RN-0263. Madison, US Department of Agriculture, Forest Products Laboratory. 46. TIMBER DEVELOPMENT ASSOCIATION OF SOUTH AUSTRALIA. Timber species (external uses). Technical information no. 7. 47. MIGONE E. & PRESTON S.B. 1955. Physical and mechanical properties of certain woods from Paraguay. Woods Technology No. 7, Ann Arbor. 48. TRADA. 1985. Timbers – their properties and uses. Wood information sheet no. 10. 49. TIMBER DEVELOPMENT ASSOCIATION LTD. Notes on East African Timbers. Timber information

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reference London.

No.

28,

College

Hill,

Research Bulletin No. 50. HMSO, London. 55. ASSOCIATION TECHNIQUE INTERNATIONALE DES BOIS TROPICAUX. 1982. Nomenclature generale des bois tropicaux. ATIBT, France. 56. GUENEAU P. (No date) Bois et Essences Malangaches. Imprimerie Societe Malagache D’edition, Tanarive. 57. GUENEAU P. & GUENEAU D. 1969. Proprietes physiques et mechaniques des bois Malagaches. Division de Technologie du Centre d Madagascar. 58. SBTC (Societe des Bois Tropicaux du Cameroun) no date. Information profile on common timbers exported from Cameroun. Douala, Cameroun. 59. TROTTER, H. 1941. The common commercial timbers of India and their uses. Government of India Press, New Delhi.

50. TIMBER DEVELOPMENT ASSOCIATION LTD. African Timbers. Timber information reference No. 33, London. 51. TIMBER DEVELOPMENT ASSOCIATION LTD. Some new timbers and their uses. Timber information reference No. 28, College Hill, London. 52. GRISA E. 1988. Anatomie ligneuse de 24 especes feuilues de la cote ouest de Madagascar. Centre de Formation Professionnelle Forestiere, Fofamplala, Morondava. 53. GUENEAU P. 1971. Bois de Madagascar possibilities d’emplois. Centre Technique Forestier Tropical, Tananarive, Madagascar. 54. LAVERS G.M. 1969. The strength properties of timbers. Forest Products

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