Tropical deforestation is being driven by cattle ranchers, palm and rubber plantations, wood manufacturers, and other industries. Teak, Ibe, and other hardwoods are harvested from tropical forests. Tropical hardwoods are in demand because of their durability. According to The Economist, harvesting these hardwoods causes damage at many levels – not only does harvesting remove the trees, but it also destroys dense wildlife habitat and a sustainable source of income for local forest residents. “It would be better to use softwood, which grows in cooler climes in sustainably managed forests.” However, softwoods aren’t naturally durable enough to be used outdoors.
Natural softwoods, if used outdoors, are chemically treated to make them harder and more durable. “The stuff is not durable enough to be used outdoors without being treated with toxic preservatives to protect it against fungi and insect pests. These chemicals eventually wash out into streams and rivers, and the wood must be retreated. Moreover, at the end of its life, wood that has been treated with preservatives in this way needs to be disposed of carefully.” The chemicals used on softwoods then also have environmental effects.
The Economist cites two firms that have developed more ecologically sustainable treatments that make softwoods more durable. Kebony, a Norwegian firm, “stops wood from rotting by placing it in a vat containing a substance called furfuryl alcohol, which is made from the waste left over when sugarcane is processed. The vat is then pressurised, forcing the liquid into the wood. Next the wood is dried and heated to 110ºC. The heat transforms the liquid into a resin, which makes the cell walls of the wood thicker and stronger.” The other firm, Titan Wood, in Holland, has developed a related technique. “Titan Wood developed a technique for converting hydroxyl groups into acetyl groups (a different combination of atoms) by first drying the wood in a kiln and then treating it with a chemical called acetic anhydride. The result is a wood that retains its shape in the presence of water, and is no longer recognised as wood by grubs that would otherwise attack it. It is thus extremely durable.”
Under the more sustainable treatment process of these firms, softwoods could be used for outdoor furniture, spas, window frames, and would also be more cost-effective compared to softwoods that need to be continually treated over their lifetime. “Kebony reckons that its pine cladding, for example, would cost a third less than conventionally treated pine cladding over the course of 40 years.” It’s now an issue of getting treated, enviromentally-friendly, recyclable softwood that is as durable as natural tropical hardwoods out to the mass market.
Also, according to The Daily Green, the U.S. International Trade Commission estimates that as much as 30 percent of hardwood products imported into the U.S. are from suspicious or illegal sources.
Learn more at the Forest Stewardship Council and World Resources Institute’s Sustainable Procurement of Wood and Paper-based Products Web site.
Image credit: Kebony ASA, Project by Inspirit / Design by Brandlab & Abono
