Ecuador, located on the western coast of South America, is the largest source of model grade balsa in the world. Balsa trees grow very rapidly, either singly or in small scattered groups in the jungle. The tree is ready to cut in 6 to 10 years at a height of 60 to 90 feet and a diameter of 12 to 45 inches.
Balsa wood is extremely light because the cells of the wood are very large and thin walled. To make the tree strong the cells fill with water. Green balsa typically contains five times as much water as actual wood substance by weight. The wood must be carefully kiln dried to remove this moisture and reduce the water content to 6% or less.