Is Balsa the lightest wood in the world?

By this article to more about the balsa wood. Finished balsa wood, like you find in model airplane kits, varies widely in weight. Balsa is occasionally found weighing as little as 4 lbs. per cu. ft. On the other hand, you can also find balsa which will weigh 24 lbs or more per cu. ft. However, the general run of commercial balsa for model airplanes will weigh between 6 and 18 pounds per cu. ft. Eight to twelve pound balsa is considered medium or average weight, and is the most plentiful. oeicoqmb Six pound or less is considered "contest grade", which is very rare and sometimes even impossible to obtain.
Is Balsa the lightest wood in the world?
No! Most people are surprised to hear that botanically, balsa rectangle  is only about the third or fourth lightest wood in the world. However, all the woods which are lighter than balsa are terribly weak and unsuitable for any practical use. The very lightest varieties don't really resemble wood at all, as we commonly think of it, but are more like a tree-like vegetable that grows in rings, similar in texture to an onion. It is not until balsa is reached that there is any sign of real strength combined with lightness. In fact, balsa wood is often considered the strongest wood for its weight in the world. Pound for pound it is stronger in some respects than pine, hickory, or even oak. Refer to chart below for comparison.
About the Chart: Weight shown is in pounds per cubic foot. The strength of balsa varies in direct relation to its density or weight — the heavier the wood, the stronger it is. The above chart was designed with 10 lb/ft³ bass polywood as the median. In other words, balsa at 10 lb/ft³ has been tested and given a value of 100. The other woods were then tested in the same way and given a figure that is numerically in proportion. By comparing the relative strength figures in the chart, it will be seen that balsa is as strong or stronger, pound for pound, than most of the species shown.