AKA: Guano, polak, topa
Description: Balsa is the lightest and softest of all woods available today (and yes, it is a hard wood). The lumber, when dry, weighs on average 11 pounds per cubic foot and often as little as 6 pounds. Because of its light weight and exceedingly porous composition, balsa is highly efficient when buoyancy, insulation against heat or cold, or sound absorption is important.
Common Use: Life-saving equipment (floats, rafts), model making (especially model aircraft).