Timber and Related Products

Switenia
Wood type Hardwood
Environmental Timber from the 'Neotropics' (Brazil, Bolivia, Costa Rica, Colombia, Mexico, Peru) is classified as endangered and lised by CITES under Appendix II. Trade is permitted subject to export permits from the country of origin (and re-export permits as appropriate) and UK import permits from the Department for Trade and Industry.
Introduction The mahoganies of Central America and the West Indies (Swietenia spp), differ among themselves to a much greater extent than do the related mahoganies of Africa (Khaya spp) These differences are attributable to geological areas of growth and whether the trees are forest-grown or plantation-grown. Nearly 400 years has elapsed since Spanish mahogany (Swietenia mahagoni) was first shipped to the UK and Europe and later to America and elsewhere, to become the most cherished cabinet wood in the world. Despite its value for cabinet-making, enormous quantities of small diameter mahogany were used annually to fire the boilers of Caribbean sugar mills and locomotives, and larger trees were felled for use as railway sleepers, fence posts and other utilitarian purposes. This indiscriminate wastage of Spanish mahogany finally resulted (1946) in the governments of Cuba, Haiti and the Dominican Republic banning the export of mahogany logs and lumber. Spanish mahogany has now become of more historical than
commercial significance. Another species, Swietenia macrophylla King filled the position formerly held by Swietenia mahagoni J'acq but world demand has led to felling at smaller diameters and to the establishment of plantations, where growth is often very rapid, and the wood less dense.
Distribution S. macrophylla occurs from southern Mexico southward along the Atlantic slope of Central America from Belize to Panama, and in Colombia, Venezuela, and parts of the upper reaches
of the Amazon and its tributaries in Peru, Bolivia and Brazil. The tree makes its best development on well-drained soils, but it does fairly well on many sites from sea level to 900.0m in altitude.

Note

Swietenia humilis Zucc. (S. cirrhata Blake.) occurs in dry locations along the Pacific coast from Western Mexico to Costa Rica. The wood is indistinguishable from that of S.macrophylla.
Swietenia belizensis Lundell. occurs in Belize and may be mixed with S. macrophylla. Swietenia candollei Pittier. Swietenia tessmannii Harms. Swietenia krukovii Gleason and Panshin. These three species are found in South America, but are generally considered to be synonymous with S. macrophylla.
The Tree Forest-grown trees are often very large, sometimes 45.0m high, with a diameter of 2.0m or more above a heavy buttress. Plantation-grown trees often make very rapid growth, frequently reaching small saw-log size in 20 years on good sites, and under average conditions, 300mm to 355mm saw-logs (diameter inside bark) are grown in about 40 years
The Timber The sapwood is generally 25mm to 50mm wide, yellowish-white in colour, sharply demarcated from the heartwood, which is pinkish or salmon coloured when freshly sawn, later becoming light reddish-brown with a golden lustre. The grain which is pinkish or salmon coloured when freshly sawn, later becoming light reddish-brown with a golden lustre. The grain is commonly interlocked, producing a wide attractive striped figure on radial surfaces. The texture is rather fine to medium,
and is uniform. Deposits of dark-coloured gum in the pores are common, and white deposits are sometimes present. Ripple marks on the tangential longitudinal surfaces can usually be observed.
Plantation-grown wood is generally somewhat less dense than forest-grown wood, the latter weighing about 560 kg/m3 and the former about 496 kg/m3 when dried. There appears to be no
appreciable difference in density and technical properties of wood from the different countries.
Drying Central American mahogany can be air dried and kiln dried rapidly and easily, without appreciable warping or checking. The presence of tension wood and gelatinous fibres is not uncommon in S. macrophylla and such wood can result in a high rate of longitudinal shrinkage during kiln drying.
Strength The strength properties are extremely good for a timber of its weight. For this reason it was at one time used almost exclusively for aeroplane propellers. Plantation-grown wood is slightly below forest-grown wood in bending strength and work to maximum load in static bending in proportion to its slightly lower density. On the other hand, plantation-grown wood is generally superior in hardness, compression across the grain and shear. In the air dry condition, plantation-grown
material is very much lower in modulus of elasticity, although both types are about equal in shock resistance.
Working Qualities Good - Good
Durability Durable
Treatability Extremely difficult
Moisture
Movement
Small
Density
(mean, Kg/m³)
560 (Density can vary by 20% or more)
DensityText Density can vary by 20% or more
Availability CITES II
Price High
Use(s) Exterior joinery, Furniture, Interior joinery
Colour(s) Reddish brown ( )