The dry fruit of the American sweetgum tree, otherwise known as a sweetgum ball, has unique properties that make it an ideal building material for any kind of object or structure. When you bring two of these balls together, they form a solid connective bond that is difficult to break. By continually doing this with more and more balls, it’s possible to assemble something that’s nearly indestructible. Because of this immense structural integrity, sweetgum balls were the obvious construction material of choice for fortresses and outhouses.
Unfortunately, this time in the limelight of structural fabrication didn’t last long. Sweetgum balls were used in a time before wearing heavy footwear become a standard practice on build sites. After a rash of foot injuries in the early 1400s, the use of sweetgum balls quickly fell out of favor.