Carapa guianensis (andiroba) as an alternative to Swietenia macrophylla (genuine mahogany).
Conclusion: Carapa guianensis, as a species that can be grown in monocrop plantations, can provide a much-needed substitute for Swietenia macrophylla, helping to take the pressure off this endangered species.
Swietenia macrophylla (“genuine mahogany,” “Honduras mahogany,” “caoba”) produces one of the finest woods in the world, and perhaps the most valuable timber in the whole of tropical Latin America. The wood is soft and easy to work using hand tools as well as mechanical tools. The wood’s specific gravity ranges from 0.40 to 0.85 (Niembro, 19921). It acquires a good polish and does not crack or bend, making it valuable in the manufacture of quality furniture.
Timber is the most valuable product of Carapa guianensis, with its specific gravity of 0.42 to 0.52 (Carpio,I.19922); the wood is stable and has multiple uses, especially for furniture. However, the wood varies because morphological and physical characteristics differ among habitats (Flores & Obando, 20033). The wood of C. guianensis (“Andiroba,” "crabwood," "Brazilian mahogany," and in Costa Rica “cedro macho” or “caobilla”) has a fine or moderate texture and a high luster; the grain is typically straight, slightly undulated, or sometimes intercrossed. It is decorative in radial planes due to ray-gold glare and the wide longitudinal lines. It is used in cabinetwork, carpentry, turnery, general construction, flooring, boxes, packing, veneer, and masts. Shoemakers use the wood to make heelpieces. C. guianensis is an excellent wood for carpentry, comparable with the wood from Cedrela odorata and Swietenia macrophylla. Many manufacturers can’t recognize the difference or they lack the experience to identify genuine mahogany, so they sell furniture made from other species like Cedrela odorata, Carapa guianensis, virola Kochnii, and Calophyllum brasilence, calling it mahogany. Despite that those woods are similar to Swietenia, they have different mechanical and physical characteristics that need to be considered before manufacturing furniture from them.
Mahogany is threatened by overharvesting for commercial trade, with more than 120,000 cubic maters exported from Latin America each year, and the United States usually gets more than 80 percent of that. The majority of mahogany entering into international trade is from unmanaged natural forests. As one of the most precious of tropical hardwoods, the high prices mahogany fetches pay for the construction of roads into areas where commercial logging would otherwise be untenable.
The high value of the timber also leads to illegal logging, inside forest concessions and outside, in parks and indigenous peoples’ reserves. Once roads are built, the forest is vulnerable to further exploitation and clearance for agriculture (Globaltrees4).
S. macrophylla is usually found in dry forests, but it also occurs in moist and gallery forests, from Mexico to Brazil and Bolivia. It is now widely planted throughout the whole of the tropics as a forest crop. Mahogany trees are reported to grow to heights of over 150 feet (46 m), with trunk diameters of over 72 inches (180 cm) above large basal buttresses.
In natural forests, the species is slow-growing, taking from 55 to 120 years to reach a commercially exploitable size; it is patchily distributed as it regenerates in forest clearings and tends to occur in even-aged stands, which are easily harvested out by loggers (IUCN5).
In plantations, it is possible to harvest Swietenia from thinnings at 10, 15, and 20 years and get the final harvest around the 25th year (Conafor & Maga, 19986).
There is some indication that mahogany is not successfully regenerating in forests following commercial harvest. Mahogany is predominantly harvested by selective logging, in which only high value trees are extracted from the forest. This practice does not create the light conditions that seem to be necessary for mahogany regeneration and removes the majority of the seed-producing trees, reducing the chances of seedling establishment (Globaltrees7).
C. guianensis grows from Belize to South America and the Antilles. In Costa Rica it grows on both slopes: on the Caribbean side and the central and southern areas of the Pacific coast (Jimenez, et al., 20028).
Andiroba is a soft, yet durable wood, and much sought by sawmills. It has in the past been shipped to the United States for use in the furniture industry and for other uses. Its durability and impalatability to insects have guaranteed commercial demand for the wood, and as a result, the species has been devastated in all areas near major towns in Amazonia. However, it could be cultivated easily.
The indigenous peoples in the Amazon have used andiroba in many ways for centuries, and virtually all parts of the tree as well as the seed oil are utilized. The oil is commercially manufactured into anti-inflammatory, antibacterial, antiarthritic, and insect repellant soaps as well as turned into candles that are sold as natural insect repellents. The oil is also used in Brazil as a furniture polish that is thought to protect wooden furniture from termites and other wood-chewing insects (Rain-tree9).
The International Tropical Timber Organization (ITTO10) reports that the species is an important source of timber. Square-edged timber is an important export material.
Andiroba timber is reported to be more abundant in supply than Honduras mahogany (Swietenia macrophylla ), and although it is not as available through hardwood suppliers in the USA and Europe as the true mahoganies (Swietenia and Khaya senegalensis), the timber of Carapa is reported to be less expensive, when available. It is more apt to be found growing in pure stands, and is reported to still occur in enough numbers to be used for construction in some areas within its natural range.
The color of the heartwood is reported to vary. It is initially light salmon to reddish brown, or pale pink to rich red-brown, but ages to a fairly uniform dull reddish brown. The wood is reported to be so similar to Honduras mahogany that they are often confused with each other, although carapa is reported to be less figured and has a finer texture than Honduras mahogany. The wood exhibits an attractive stripe and parallel, irregular rays when quartersawn. It is a heavy wood with high density.
Slow drying rates are recommended; and a low temperature, high humidity schedule is suggested for best results. The timber is reported to be more difficult to dry than Honduras mahogany.
Andiroba timber is reported to be dimensionally stable after drying and exhibits only small movement in use. Weathering characteristics are reported to be comparable to those of the mahoganies (Swietenia and Khaya, or African mahogany). Cutting resistance is low and the wood is reported to have satisfactory sawing characteristics.
Andiroba is reported to be easy to plane, but a reduced angle of 15 degrees is recommended when working material with interlocked grain. It is reported to be more difficult to work than either Honduras or African mahogany since it is more dense. The wood can be molded or shaped easily. The timber is reported to exert a slight to moderate blunting effect on cutting tools. The wood turns well and has been compared to sugar maple and cherry in that respect.
Mortising characteristics are reported to be good. The material carves and glues well. Andiroba is reported to respond well to sanding and to polish to a smooth finish. Screwing qualities also seem to be good.
Andiroba is reported to require fewer coats of stain to achieve the same surface smoothness as Honduras mahogany. Varnishing properties are rated higher than those of Honduras mahogany. Response to hand tools is reported to be good.
The bending strength of air-dried wood is similar to that of teak, which is considered to be strong. Compression parallel to grain is in the high range. Strength properties, especially stiffness, are rated as higher than those of Honduras mahogany. Hardness is rated as medium. It resists denting and marring about as well as white oak.
Attempts to create monocrop plantations of mahogany have mostly failed because an insect known as the mahogany shoot-borer, Hypsipyla grandella, destroys the terminal shoots of the seedlings. According to the lumber industry, this leads to trees with excessive branching and poor form. Mahogany does better if planted within a teak planting, at no more than 51 to 66 trees per hectare.
Andiroba, on the other hand, does grow in monospecific plantations with distances of more than 3 m between trees. The species growth has been reported as 4.3 m in height and 4.6 DBH after 3 years, and 12.6 cm DBH and 11.1 m high at 9 years of age. In addition, this species can survive after seasonal flooding.
1www.globaltrees.org . 14 th Nov. 2005 & 17th Nov. 2005
2www.iucn.org/webfiles/doc/ . 21st Nov. 2005
3www.conafor.gob.mx/programas_nacionales_forestales/ , and Ministerio de Agricultura Ganaderia y Alimentacion (MAGA), 1998. Sistemas para la selección de especies forestales. Guatemala, Plan de acción forestal para Guatemala (MAGA), GCP/GUA/007/NET.
4www.globaltrees.org . 15 th Nov. 2005
5Jiménez, Q. et al . Árboles maderables de Costa Rica, Ecología y Silvicultura. Editorial Inbio y E. Tecnológica de CR., 2002. p.70.
6www.rain-tree.com/andiroba 15 th Nov. 2005 & 17th Nov. 2005
7www.arkive.org/species/GES/ . Appendix II of the Convention on International Trade in Endangered Species in 2002. 17 th and 21st Nov. 2005 .
8Niembro Rocas, Anibal. Swietenia macrophylla King, in Tropical Trees Seed Manual, USDA, Forest Service, Agriculture Handbook 721, October 2002. 722-723.
9Carpio, Isabel. Maderas de Costa Rica: 150 especies forestales. 1era Edic. San José, Costa Rica, Edit. Univ. De Costa Rica, 1992 p 66.
10Flores, E. & Obando, G. Árboles del Trópico húmedo. Importancia socioeconómica. Editorial Tecnológica de CR. 2003. 217-221.