Balsa Wood and Its Uses.
The wood of the Balsa tree (Ochroma pyramidale) is remarkably light, very strong, cuts well and does not bend or warp easily. It comes from one of the fastest growing trees in the tropical forests and humid rain forests of Central and South America and can grow 4 metres in one year. It can even reach a height of 30 metres. Because the Balsa tree grows so fast most of the cells of which the wood is made remain thin-walled. After the Balsa tree is cut down these cells die and they begin to expand with air. This makes the wood incredibly light and can even weigh less than cork. The Balsa tree has large grey-green leaves and can be as wide as half a metre across. The bark of the tree trunk is a smooth, marbled texture. Balsa trees tend to grow on their own or in small groups scattered widely through the forests.
The name Balsa comes from the Spanish word for raft as it was often used by the people of South America to make canoes and rafts. One famous raft made from Balsa wood was that of the Norwegian, Thor Heyerdahl in 1947. He and five others called their raft Kon-Tiki and sailed 4,300 miles across the Pacific Ocean from Peru, in South America, to an island in the Pacific group known then as the Tuamotu group. This proved that the Peruvian indians could have migrated to the Polynesian islands. More recently, Balsa wood was used more and more in model making particularly model aircraft, surfboards and boats. In fact, Balsa wood was used in the manufacture of the world war two fighter plane, the de Havilland Mosquito. It has also been used in the making of table tennis bats where a layer of Balsa wood is sandwiched between two pieces of thin plywood. The wood is not quite the lightest in the world but it is the strongest of the lightweight woods.