Agroforestree Database

Local names:
 Bengali (bara mahauni,bara-mahagoni,mahagni), Dutch (mahonie,mahok), English (Dominican mahogany,bastard mahogany,big-leaf mahogany,Brazilian mahogany tree,Colombian mahogany tree,Honduras mahogany,large-leaved mahogany,Mexican mahogany tree,West Indian

Swietenia macrophylla is a very large tree, reaching a height of 30-40 m and a girth of 3-4 m; in favourable conditions it can reach 60 m high and 9 m girth. Trunk straight, cylindrical, with a buttressed base; bark rough, flaking off in small patches.

Leaves paripinnate, up to 60 cm long; leaflets 6-16, ovate, lanceolate, acuminate, slightly oblique, light green or reddish when young, dark green and shining when mature, up to 20 cm long, with 8-12 pale, secondary nerves.

Flowers 8 mm across, in narrow supra-axillary panicles about 8-13 cm long and fragrant; petals greenish-white, oblong, 4 mm long, rigidly pointed.

Fruit a woody capsule resembling a large inverted club, about 12.5 x 7.5 cm, erect.

‘Swietenia’ commemorates Gerard von Swieten (1700-1772), botanist and physician to Maria Theresa of Austria. The specific name, ‘macrophylla’, means large leaved and comes from Greek words ‘makros’ (large) and ‘phyllon’ (leaf).

Ecology

S. macrophylla is found in all forest types, from the edge of the pine savannah to the climax rainforest, but mostly in mixed hardwood forest belts, along riverbanks, on deep alluvial soils of considerable fertility. It occurs scattered or in small groups, but densities of more than 4-8 trees/ha are rarely encountered. In tropical America, it is among the pioneer species reoccupying degraded agricultural land. It has been shown that teak is outcompeted by S. macrophylla in a mixed stand. In the Philippines, S. macrophylla is reported to be very firm in wind, resistant to cyclones.

The species has some weed potential and may invade native forest communities, especially following disturbance. It should not be planted in close proximity to areas of high nature conservation significance.

Native range
Belize, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, Venezuela

Tree management

Young trees are fairly tolerant to shade, but conditions for optimum growth call for full overhead light combined with side protection. In natural stands, therefore, it is beneficial to open the canopy over dense, young regeneration in which saplings are about 1.8 m high. In plantation forestry, S. macrophylla has always been planted at 10 x 3 m (333 stems/ha), because it requires large amounts of light. Plantations established at such wide spacing rarely need thinning unless selectively to remove diseased stems. The tree is self-pruning and further pruning is not necessary. When grown for timber, S. macrophylla has a rotation age of 30-35 years, with a final stocking rate of 150-250 stems/ha.

Despite widespread suggestions to the contrary, seeds of this species are not recalcitrant but are probably intermediate; 2.5% of seeds germinated following 2 years of hermetic storage with dry seeds at 3-5 deg. C. Viability can be maintained for 1 year in hermetic storage. No loss in viability occurs after storage for 7 months at 12 deg. C with 9% mc. Seeds tolerate desiccation to 5%. There are about 2400 dewinged seeds/kg.

S. macrophylla is found in all forest types, from the edge of the pine savannah to the climax rainforest, but mostly in mixed hardwood forest belts, along riverbanks, on deep alluvial soils of considerable fertility. It occurs scattered or in small groups, but densities of more than 4-8 trees/ha are rarely encountered. In tropical America, it is among the pioneer species reoccupying degraded agricultural land. It has been shown that teak is outcompeted by S. macrophylla in a mixed stand. In the Philippines, S. macrophylla is reported to be very firm in wind, resistant to cyclones.

The species has some weed potential and may invade native forest communities, especially following disturbance. It should not be planted in close proximity to areas of high nature conservation significance.

Fruiting can sometimes be heavy, and mature trees can produce copious seed crops. Mature fruits can be collected directly from trees by climbing them. Fruit is placed in open trays in a well-ventilated, shaded area and beaten by hand against a hard surface. The seed is separated and the wings gently broken off by hand, then further dried to about 6-8% mc. In Haiti, most farmers who plant out seedlings do so from naturally regenerated stock from the field. No seed pretreatment is required. Germination of fresh seed normally commences 10-17 days after sowing, and the germination rate is high at over 90%.

S. macrophylla has been used in reforestation projects and has proved to be suitable in areas not protected from grazing.

Timber:  The high value attached to S. macrophylla wood in the international markets is well known. The heartwood is red-brown in appearance. The density of the wood of plantation-grown trees is often somewhat less than that of trees from the forest in the natural area of distribution and weighs 485-840 kg/m³ at 12% mc. The wood has been used in interior panelling, joinery work, turnery, furniture, plywood and heavy construction work. Veneer quality is limited by colour variation, wavy grain, pin knots and pinhole borer damage.

Shade or shelter:  S. macrophylla is used as a shade tree, for example, for young plantations of dipterocarps.

Tannin or dyestuff:  The bark is used for dyeing and tanning leather. 

Lipids:  An oil that might be of some commercial value can be extracted from the seed kernels.

Medicine:  Various medicinal uses of parts of the tree are reported from Central America.

Gum or resin:  A gum is produced from cuts in the bark for markets in Bombay, India, it is marketed in both pure form and mixed with other gums. 

Ornamental:  Planted as a lawn tree in peninsular Malaysia.

Soil improver:  The crushed fruit shells have been used as a potting medium.

Intercropping:  The value of S. macrophylla as an undercrop for teak (Tectona grandis), to facilitate heavy thinning of the latter without exposing the soil to the risk of serious desiccation and erosion, is quite promising and worth great consideration. In Puerto Rico, farmers have planted S. macrophylla among subsistence crops such as corn, beans, bananas, sweet potatoes and cassava.