Swietenia macrophylla (PROTA) - PlantUse English

Swietenia macrophylla (PROTA) – PlantUse English

distribution in Africa (planted)

1, tree behavior; 2, flowering twig; 3, sectioned male flower; 4, sectioned feminine flower; 5, fruit; 6, seed. Supply: PROSEA

bark, leaf and fruits (College of Hawaii)

wooden in transverse part

wooden in transverse part

wooden in tangential part

wooden in tangential part

transverse floor of wooden

Swietenia macrophylla King

Protologue: Hook.f., Icon. pl. 16: t. 1550 (1886).
Household: Meliaceae
Chromosome quantity: 2n = 24, 46, 54, 108

Vernacular names

  • Large-leaved mahogany, large-leaved mahogany, broad-leaved mahogany, Honduras mahogany (En).
  • Acajou du Honduras, acajou d’Amérique, mahogany grandes feuilles (Fr).
  • Mogno (Po).

Origin and geographic distribution

Swietenia macrophylla is native to the mainland of Central and South America, from Mexico to Peru, Bolivia and Brazil, which makes it probably the most broadly distributed Swietenia species. The wooden has been internationally traded for over 400 years. Large-leaved mahogany was launched in India from Belize in 1872, and has since been planted all through the tropics in timber plantations and as a decorative, additionally on a small scale in tropical Africa. Makes an attempt to introduce mahogany to tropical Africa (e.g. in Sierra Leone, Nigeria, Uganda) have been largely unsuccessful as a result of severity of shoot borer assault on younger vegetation. Trial plantations in Mauritius have been initially unsuccessful, however later Swietenia macrophylla was used efficiently for reforestation at low elevations. Intensive plantations exist in Indonesia, Fiji and Sri Lanka.

Makes use of

Swietenia wooden (mahogany) is considered the world’s most interesting timber for high-class furnishings and cupboard work. Its recognition is particularly attributable to its engaging look together with ease of working, glorious ending qualities and dimensional stability. Additionally it is typically used for inside trim corresponding to panelling, doorways and ornamental borders. It’s used for boat constructing, typically as an ornamental wooden for luxurious yachts and ocean liners, however generally additionally as plywood for planking and deck housing. Its excellent technical qualities make it notably appropriate for precision woodwork corresponding to fashions and patterns, instrument circumstances, clocks, printer’s blocks and components of musical devices; for these functions, uniform straight-grained materials is used. Different minor makes use of embody burial caskets, wooden carvings, novelties, toys and turnery.

An oil, which may be very bitter and purgative, could be extracted from the seeds, however business exploitation of the oil appears unlikely. The bark is bitter and astringent, and has been used as a febrifuge and in addition for dyeing and tanning leather-based. A gum is produced for Bombay (India) markets from cuts within the bark, the place it’s bought each pure and combined with different gums. Numerous medicinal makes use of of assorted components of the tree are reported from tropical America. The crushed fruit shells have been used as a potting medium. Swietenia macrophylla can be utilized in reforestation programmes and agroforestry methods, and as a shade tree in younger plantations of different timber species, and is sometimes planted as decorative.

Manufacturing and worldwide commerce

Mahogany is among the most essential tropical timbers on the world market. Most mahogany traded is from pure stands, and solely small portions can be found from planted bushes. The annual export from tropical America exceeds 120,000 m³. In 1996–2002 the typical annual export of Swietenia macrophylla timber was 59,500 m³ from Brazil, 30,500 m³ from Peru, 15,000 m³ from Bolivia and 14,000 m³ from international locations in Central America. In 2002 the value of sawn Swietenia macrophylla timber from Bolivia was about US$ 980/m³. An important importer is america with an import of 76,000 m³/yr, which is over 60% of worldwide commerce. It has been estimated that the realm planted with Swietenia macrophylla within the tropics is 200,000 ha, however the space in Africa is insignificant.

Properties

The heartwood is reddish or pinkish, the color darkening with age to a deep pink or brown, distinctly demarcated from the normally yellowish sapwood, which is as much as 40 mm vast. The grain is interlocked, generally straight, texture wonderful to reasonably coarse. The surfaces are shiny, with golden lustre, and the wooden is usually properly figured due to irregular grain.

Large-leaved mahogany wooden is a medium-weight wooden. The density is (450–) 530–670(–840) kg/m³ at 12% moisture content material, with that of plantation-grown bushes typically considerably lower than that of bushes from pure forest. The charges of shrinkage are low, from inexperienced to 12% moisture content material 1.4% radial and a pair of.2% tangential, and from inexperienced to oven dry 2.1–3.3% radial and a pair of.9–5.7% tangential. The wooden seasons properly, with out a lot checking or distortion. Planks of 50 mm thick could be air dried in 11 weeks from 40% moisture content material to 15%, boards of 25 mm thick in 6 weeks. The wooden kiln dries satisfactorily when average schedules are used (temperatures of 43–76°C and corresponding relative humidities of 75–33%). Planks of 50 mm thick could be kiln dried in roughly Eight days from 40% moisture content material to 15%, and boards of 25 mm in Four days. Planks of 41 mm thick could be kiln dried in 13 days from 70% moisture content material to 15%. After drying, the wooden is steady in service.

The wooden is relatively mushy. At 12% moisture content material the modulus of rupture is 72–98 N/mm², modulus of elasticity 9300–12,100 N/mm², compression parallel to grain 43–62 N/mm², shear 13.5 N/mm² and Janka facet hardness 3560 N.

The wooden saws, planes and moulds simply in each inexperienced and dry situation. Normally it finishes to a easy floor, however a woolly floor might happen on bands of response wooden or interlocked grain. Ending is straightforward and the wooden takes a wonderful polish. Gluing and nailing properties are good, however discoloration involved with iron, copper and brass might happen underneath humid circumstances. The wooden slices and rotary cuts into wonderful and ornamental veneer, with out preliminary remedy, at a peeling angle of 92°. The veneer could be glued with casein prolonged with 30% lime, to provide plywood of passable high quality. Passable outcomes are obtained with pulping (kraft pulp yield of 49.5%).

The heartwood of bushes from pure stands could be moderately sturdy, however it isn’t thought-about appropriate for purposes involved with the bottom. Graveyard checks in Indonesia confirmed a median service life involved with the bottom of two.7 years. The wooden is proof against wood-rotting fungi. The sapwood is vulnerable to Lyctus borer assault and the heartwood may additionally be attacked by pinhole borers and termites; the wooden has little resistance to marine borers. The wooden is proof against impregnation with preservatives by strain strategies, however plantation-grown wooden could be amenable to boron diffusion strategies.

The wooden comprises 39–47% cellulose, 27–31% lignin, 16–18% pentosan, 0.5–0.6% ash and 0.1% silica. The solubility is 2.4% in alcohol-benzene, 0.4% in chilly water, 4.5% in sizzling water and 19% in a 1% NaOH answer. The power worth of the wooden is 19,600–20,300 kJ/kg. The wooden comprises important oil which is wealthy in sesquiterpenes. The bark of Swietenia macrophylla confirmed important in-vivo antimalarial exercise in checks with rodents.

Adulterations and substitutes

True mahogany timber from Swietenia spp. is hardly produced in tropical Africa, however the timber of a number of indigenous and roughly associated species is traded as African mahogany, primarily Entandrophragma and Khaya spp., which produce wooden with comparable traits.

Description

  • Medium-sized to giant monoecious tree as much as 40(–60) m tall; bole normally straight and cylindrical, branchless for as much as 18(–25) m, as much as 150(–200) cm in diameter, typically with broad and plank-like buttresses as much as 5 m excessive; outer bark of older bushes scaly, shaggy, deeply longitudinally furrowed and brownish gray to reddish brown, inside bark red-brown or pinkish pink; crown dome-shaped, consisting of some giant, ascending branches.
  • Leaves alternate, paripinnate with (2–)3–6(–8) pairs of leaflets; stipules absent; leaflets reverse, ovate-elliptical, 8–18 cm × 3–5.5 cm, whole, glabrous, pinnately veined.
  • Inflorescence an axillary panicle 10–20 cm lengthy, consisting of small cymes.
  • Flowers unisexual, however with well-developed vestiges of the other intercourse, common, 5-merous, small; pedicel slender, 1.5–2.5 mm lengthy; calyx with broadly rounded lobes 1–1.5 mm lengthy, bushy at margins; petals free, barely contorted in bud, ovate-oblong, 5–6 mm lengthy, bushy at margins; stamens united right into a tube, with 10 sessile anthers on the mouth of the tube; disk annular; ovary superior, normally 5-celled, type quick, with disk-shaped stigma.
  • Fruit a woody, elongate-ovoid capsule 10–15(–22) cm lengthy, greyish brown, opening by 5 valves, many-seeded.
  • Seeds with giant wing, flat, 7.5–10 cm lengthy, darkish brown, hanging down and overlapping in fruit; cotyledons skinny.
  • Seedling with hypogeal germination; first Three leaves easy, later ones 3-foliolate or imparipinnate.

Different botanical data

Swietenia contains Three species and is most intently associated to Khaya, which differs in its extra globose fruits and seeds narrowly winged all around the margin. The three Swietenia species are tough to differentiate from one another. Swietenia macrophylla differs from Swietenia mahagoni (L.) Jacq. in its bigger leaflets, fruits and seeds, and from Swietenia humilis Zucc. in its stalked and shortly acuminate leaflets (sessile and long-acuminate in Swietenia humilis) and darkish brown seeds (pale brown in Swietenia humilis). The pure distribution areas of the three species present solely very slight overlap, however in areas the place 2 species happen hybrids could also be discovered.

Swietenia humilis

Swietenia humilis has additionally been launched in a number of locations in tropical Africa (e.g. in Malawi). It’s a small to medium-sized tree as much as 20 m tall, originating from Central America. Its timber is of little financial significance.

Anatomy

Wooden-anatomical description (IAWA hardwood codes):

  • Development rings: (1: development ring boundaries distinct); (2: development ring boundaries vague or absent).
  • Vessels: 5: wooden diffuse-porous; 13: easy perforation plates; 22: intervessel pits alternate; (23: form of alternate pits polygonal); 24: intervessel pits minute ( Four μm); 30: vessel-ray pits with distinct borders; just like intervessel pits in dimension and form all through the ray cell; 42: imply tangential diameter of vessel lumina 100–200 μm; (46: 5 vessels per sq. millimetre); 47: 5–20 vessels per sq. millimetre; 58: gums and different deposits in heartwood vessels.
  • Tracheids and fibres: 61: fibres with easy to minutely bordered pits; 65: septate fibres current; 66: non-septate fibres current; 69: fibres thin- to thick-walled.
  • Axial parenchyma: 78: axial parenchyma scanty paratracheal; 79: axial parenchyma vasicentric; 89: axial parenchyma in marginal or in seemingly marginal bands; 93: eight (5–8) cells per parenchyma strand; 94: over eight cells per parenchyma strand. Rays: 97: ray width 1–Three cells; (98: bigger rays generally 4- to 10-seriate); 106: physique ray cells procumbent with one row of upright and/or sq. marginal cells; 115: 4–12 rays per mm.
  • Storied construction: (118: all rays storied); (122: rays and/or axial components irregularly storied).
  • Secretory components and cambial variants: 131: intercellular canals of traumatic origin.
  • Mineral inclusions: (136: prismatic crystals current); (137: prismatic crystals in upright and/or sq. ray cells); (141: prismatic crystals in non-chambered axial parenchyma cells); (142: prismatic crystals in chambered axial parenchyma cells).

(E. Uetimane, H. Beeckman & P.E. Gasson)

Development and improvement

Wholesome seeds begin germinating about 10 days after sowing. Younger bushes have straight and slender stems, and branches are fashioned 2–Three m above the bottom with a place indirect to the principle stem. Nonetheless, an unbranched stem as much as 10 m tall could also be fashioned earlier than branching. Preliminary development is quick, relying on website circumstances. Underneath optimum circumstances, seedlings might attain Three m in a single yr and 6 m in two years. The typical peak of 2-year-old seedlings in experimental plantations in Nigeria firstly of the 1960s was 2 m, however there is no such thing as a data on development after 2 years. The seedlings and saplings are illiberal of deep shade though they are going to survive. Timber planted within the open discipline underneath optimum circumstances might sometimes attain 50 cm in diameter in 25 years. In forest within the pure distribution space, bushes tackle common 105 years to achieve a bole diameter of 80 cm, however the common diameter development in pure forest has additionally been estimated at 0.Four cm/yr. In well-managed stands it might be as much as 1.Four cm/yr. The utmost increment in peak happens at an age of 5–15 years, in diameter at 5–10 years and in timber quantity at 20–25 years. Buttresses start to develop quickly, typically already when the bole diameter is simply 10 cm. Timber of 200 years previous with a log diameter as much as 190 cm and timber quantity as much as 29.5 m³ have been recorded.

Underneath beneficial circumstances, younger bushes might begin to flower and produce seed when 12 years previous, hardly ever already when Eight years previous, however underneath pure circumstances profuse manufacturing of seed is way later. Flowering bushes have about 10 instances as many male as feminine flowers, however the flowers of each sexes are very comparable. Timber are generally functionally dioecious. In combined inflorescences, male flowers open first, however self-pollination might happen. The flowers are most likely pollinated by bees and moths, and outcrossing is the rule. Fruits could also be produced annually, and mast manufacturing of seeds happens irregularly. Mature fruits could be discovered 10–11 months after flowering. The seeds are supplied with a skinny tail-like wing that makes them rotate after they fall, and are thus dispersed by wind sometimes so far as 500 m from the mom tree.

Ecology

Underneath pure circumstances big-leaved mahogany thrives in each deciduous and evergreen rain forest and happens scattered or in small teams, however greater than 4–Eight mature bushes per ha are hardly ever encountered. It has been claimed that underneath pure circumstances it regenerates in primarily even-aged stands after catastrophic disturbances of the forest, e.g. hurricanes, fireplace and flooding. Grownup mahogany bushes might survive such occasions due to their robust buttresses and resistance to fireside, and unfold their seeds into the ensuing gaps or clearings. Nonetheless, it has additionally been demonstrated that big-leaved mahogany doesn’t require gaps for seed germination, most likely besides in evergreen forest the place little gentle penetrates by way of the cover.

The optimum annual rainfall is 1400–2500(–3500) mm with a dry interval of 0–Four months. Swietenia macrophylla grows from sea-level to 1500 m altitude, in areas with a imply annual temperature of 20–28°C, the vary of the coldest and warmest month being 11–22°C and 22–30°C, respectively. It’s largely unspecific as to soil necessities. Inside its pure vary it has been discovered on alluvial soils, volcanic soils, heavy clays, lateritic soils, soils derived from limestone, granite and different sedimentary, igneous or metamorphic rock formations and even on shallow rendzinas. In plantations it performs finest on deep, fertile, well-drained soils with a pH of 6.5–7.5. It doesn’t tolerate waterlogging. In tropical America mahogany is among the many pioneer species reoccupying degraded agricultural land. It has been proven that teak is outcompeted by mahogany in a combined stand.

Propagation and planting

Fruits have to be collected when ripe to realize a very good germination charge. The fruits open after 2 days of storage and the seeds are very viable with a germination charge of 60–95%. The seeds could be saved as much as 2 months, or longer (as much as one yr) if saved cool (2–5°C) in sealed containers at about 45% relative humidity. The load of 1000 seeds is 400–500 g.

Seeds are sown within the nursery in drills of two–Four cm deep, or they’re pushed into flat beds, leaving a part of the wing uncovered. Seed germination begins after about 10 days and continues for about 20 days. The seed mattress must be properly manured and shaded, however after 3–Four weeks the seedlings develop finest in full daylight. Seedlings might have a 70% survival charge, even when planted in the course of the dry season, supplied they’re partially shaded and watered at any time when soil moisture drops under 30%. For discipline planting, bare-root inventory, balled seedlings, stumps (stem size 20 cm, root size 20–40 cm, diameter of root collar 0.5–2.5 cm) or striplings are used. Balled seedlings of three–Four months previous are most well-liked. Cuttings are comparatively simple to determine from 3-year-old vegetation, however tougher later. Swietenia macrophylla could be propagated by in-vitro tradition and grafting; the latter methodology has been used to determine seed orchards. Spacing within the discipline is normally 2.5–Three m × 2.5–Three m. Profuse pure regeneration has been discovered in lots of mature mahogany plantations, and this can be used to determine the following crop, decreasing nursery and plantation institution prices.

Administration

Though pure regeneration in Swietenia macrophylla stands could also be plentiful, it’s common to plant seedlings raised in nurseries. One-year-old seedlings attain optimum peak and diameter development when fertilized with 3.6 g N, 2.Four g P2O5 and three.6 g Ok2O. Phosphorus seems to be probably the most limiting aspect for seedling development.

Monoculture plantations of mahogany are vulnerable to pests, and for that motive combined plantations with different fast-growing species are sometimes most well-liked. Thinning normally begins 6 years after planting, and progressively reduces the variety of bushes to 220–400 bushes/ha in plantations of 20 years previous, and to 120–150 bushes/ha in 35-year-old plantations. The rotation is normally 40–60 years.

Illnesses and pests

A number of fungal illnesses have an effect on seedlings in tropical Asia and islands of the Pacific, however these hardly ever trigger severe harm. Shoot-boring moths of the genus Hypsipyla are the key limitation to plantation institution, and that is additionally the case in tropical Africa, the place Hypsipyla robusta can be a serious pest in Entandrophragma and Khaya plantations. Assault by Hypsipyla could be efficiently managed with pesticides underneath nursery circumstances. Ambrosia beetles might assault the wooden, creating ‘ pin-holes’ seen in sawn timber. Termites may additionally trigger harm in plantations.

Harvesting

Mahogany plantations are clear-cut when the rotation age (40–60 years) or a log diameter of 50 cm have been reached, and subsequently replanted with nursery-raised seedlings.

Yield

In rotations of 50–60 years, common annual quantity increments of 15–20 m³/ha could be achieved for plantations, on poor websites 7–11 m³/ha.

Dealing with after harvest

Mahogany logs float in water and could be transported by river. The sapwood is vulnerable to staining; an anti-sapstain dip must be used throughout drying.

Genetic sources

Populations of mahogany have been depleted by way of centuries of business exploitation in Central and South America. Though it’s widespread, Swietenia macrophylla has change into uncommon in components of its pure space of distribution. It has been included in Appendix II of CITES since 2003, along with the opposite two Swietenia species, which have been already included. This makes it topic to strict laws regarding export and commerce; exporting international locations are required to confirm that every cargo was legally acquired and that the harvest was non-detrimental to the survival of mahogany. In Brazil Swietenia macrophylla has been exploited just for the nationwide market since 2003, and the minimal diameter restrict for exploitation has been raised from 40 cm to 60 cm. There isn’t any restriction for commerce and export of plantation-grown timber. In checks in Central America utilizing seedlings raised from seed of various origin, important variation has been discovered each inside and between Swietenia macrophylla populations, notably by way of peak development and susceptibility to pest assault. An evaluation of the genetic variety in and between populations in Brazil confirmed excessive variation. Nonetheless, an evaluation of the genetic variety in Costa Rica indicated little or no gene movement.

Breeding

Choice work has been carried out on an experimental scale (e.g. in Indonesia), particularly in direction of enhancing development and germination charges. Synthetic hybridization between Swietenia spp. is feasible, and hybrids typically present promising options, combining as an example the quick development of Swietenia macrophylla and the superior-quality wooden of Swietenia mahagoni, and having higher resistance to illnesses and pests.

Prospects

A serious downside in mahogany plantations is the susceptibility to Hypsipyla assault. Analysis precedence must be given to the collection of resistant bushes that are fast-growing and have a suitable wooden high quality. The institution of optimum strategies of vegetative propagation is urgently wanted. In-vitro micropropagation strategies have already been developed, and these provide prospects for the multiplication of pest-resistant genotypes. Developments in analysis and breeding of mahogany must be intently monitored as a result of they might provide new alternatives for the institution of mahogany plantations in tropical Africa, along with African mahogany (Entandrophragma and Khaya) and in addition within the gentle of the profitable Swietenia plantations in tropical Asia and islands of the Pacific Ocean.

Main references

  • Blundell, A.G., 2004. A evaluate of the CITES itemizing of big-leaf mahogany. Oryx 38(1): 84–90.
  • Brown, N., Jennings, S. & Clements, T., 2003. The ecology, silviculture and biogeography of mahogany (Swietenia macrophylla): a vital evaluate of the proof. Views in Plant Ecology, Evolution and Systematics 6(1–2): 37–49.
  • ITTO, 2004. Making the mahogany commerce work. Report of the workshop on capability constructing for the implementation of the CITES Appendix-II itemizing of mahogany. ITTO Technical Sequence No 22. Worldwide Tropical Timber Group. 54 pp.
  • Mayhew, J. & Newton, A.C., 1998. The silviculture of mahogany. CAB Worldwide, Wallingford, Oxon, United Kingdom. 226 pp.
  • Prawirohatmadjo, S., Suranto, J., Keating, W.G., Ani Sulaiman, & Sosef, M.S.M., 1993. Swietenia Jacq. In: Soerianegara, I. & Lemmens, R.H.M.J. (Editors). Plant Sources of South-East Asia No 5(1). Timber bushes: Main business timbers. Pudoc Scientific Publishers, Wageningen, Netherlands. pp. 442–447.
  • World Agroforestry Centre, undated. Agroforestree Database. [Internet] World Agroforestry Centre (ICRAF), Nairobi, Kenya. http://www.worldagroforestry.org/ Websites/TreeDBS/ aft.asp. April 2005.

Different references

  • Burkill, H.M., 1997. The helpful vegetation of West Tropical Africa. 2nd Version. Quantity 4, Households M–R. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 969 pp.
  • Helgason, T., Russell, S.J., Monro, A.Ok. & Vogel, J.C., 1996. What’s mahogany? The significance of a taxonomic framework for conservation. Botanical Journal of the Linnean Society 122: 47–59.
  • Lamb, F.B., 1966. Mahogany of tropical America, its ecology and administration. The College of Michigan Press, Michigan. 220 pp.
  • Lowe, A.J., Jourde, B., Breyne, P., Colpaert, N., Navarro, C., Wilson, J. & Cavers, S., 2003. Fantastic scale genetic construction and gene movement inside Costa Rican populations of mahogany (Swietenia macrophylla). Heredity 90(3): 268–275.
  • Richter, H.G. & Dallwitz, M.J., 2000. Business timbers: descriptions, illustrations, identification, and knowledge retrieval. [Internet]. Model 18th October 2002. http://delta-intkey.com/wooden/index.htm. April 2005.
  • Snook, L.Ok., 1996. Catastrophic disturbance, logging and the ecology of mahogany (Swietenia macrophylla King): grounds for itemizing a serious tropical timber species in CITES. Botanical Journal of the Linnean Society 122: 35–46.
  • Types, B.T., 1981. Swietenioideae. In: Pennington, T.D. (Editor). Meliaceae. Flora Neotropica. Monograph No 28. New York Botanical Backyard, New York, United States. pp. 359–418.
  • Tillier, S., 1995. Le mahogany grandes feuilles en Martinique. Bois et Forêts des Tropiques 244: 55–65.
  • Weaver, P.L. & Francis, J.Ok., 1988. Development of teak, mahogany and Spanish cedar on St. Croix, U.S. Virgin Islands. Turrialba 38(4): 308–317.
  • Yao, C.E., 1981. Survival and development of mahogany (Swietenia macrophylla King) seedlings underneath fertilized grassland situation. Sylvatrop 6(4): 203–217.

Sources of illustration

  • Prawirohatmadjo, S., Suranto, J., Keating, W.G., Ani Sulaiman, & Sosef, M.S.M., 1993. Swietenia Jacq. In: Soerianegara, I. & Lemmens, R.H.M.J. (Editors). Plant Sources of South-East Asia No 5(1). Timber bushes: Main business timbers. Pudoc Scientific Publishers, Wageningen, Netherlands. pp. 442–447.

Creator(s)

  • R.H.M.J. Lemmens, PROTA Community Workplace Europe, Wageningen College, P.O. Field 341, 6700 AH Wageningen, Netherlands

Appropriate quotation of this text

Lemmens, R.H.M.J., 2005. Swietenia macrophylla King. In: Louppe, D., Oteng-Amoako, A.A. & Brink, M. (Editors). PROTA (Plant Sources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. Accessed 12 November 2020.

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