One of George Washington’s masterful farming innovations was a 16-sided barn designed for treading wheat—his most important cash crop. Traditionally, wheat was threshed by hand, a slow and arduous process of beating the wheat to break the grain out of the straw. Sometimes horses treaded wheat by trampling it on the ground, but that practice was unsanitary and exposed the grain to weather. Washington decided to move the threshing process indoors and in 1793 built a barn for this purpose. It was completed two years later. Horses trotted in a circle on the second floor, treading on grain that then fell to the first floor through narrow gaps in the flooring. Although Washington was in Philadelphia serving as president while the barn was under construction, he supervised the work from afar. He even calculated (correctly) that the number of bricks needed to complete the first floor would be 30,820.
The barn at the Farm site is an exact replica of the original, based on careful examination of Washington’s drawings and plans from the 1790s as well as on a mid-19th-century photograph showing the barn in a semi-ruined state.