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George Washington's 16-Sided Treading Barn

The 16-sided treading barn is George Washington’s very own invention and is used for processing wheat.

Overcoming the Challenge of Wheat Farming

When Washington switched from tobacco to wheat as his cash crop, he faced the challenge wheat farmers have always encountered—how to separate the wheat berry from the top of the wheat stalk.

After wheat was harvested, the common way to separate the wheat berry from the stalk was to thresh the wheat with a flail. A laborer would literally beat the grain to separate it from the straw.

Another way to thresh wheat was to use livestock. The animals would walk over the sheaves of wheat, and the impact of their hooves would separate the grain from the straw. This was called "treading." 

Treading was done outdoors, which exposed the wheat to the elements and mixed dirt in with the grain. A significant portion of the grain was ruined or lost as a result. Processing the wheat out of doors also left the crop exposed to fast-moving thunderstorms that could ruin a crop in moments. Washington could very well lose up to 20 percent of his harvest to soil and sky.

Daily demonstrations at the reconstructed treading barn are conducted from late summer through the fall. (MVLA)

Innovative Wheat Treading

The barn's two-story structure with one-and-a-half-inched gapped floorboards allows seeds to break free of the stalks and fall through the floorboards to the clean granary floor below. (MVLA)

The brilliance of the 16-sided treading barn was taking the most efficient method of processing horsepower/treading and moving it under cover. The other unique quality of the barn was its two-story structure with one-and-a-half-inched gapped floorboards on the top level where an acre’s worth of wheat could be laid down for horses to trot on.

The horses were led up the ramp and immediately put into a trot for 30 to 45 minutes. Their hooves knocked 90 percent of the seed from the top of the stalk down through the floorboards to the clean wooden granary floor below.

Only 10 percent of the straw escaped through the floorboards, keeping 90 percent of that waste on the treading floor.

Once the seed had fallen to the granary floor below, it was swept up, and the seed was separated from the chaff in a process called "winnowing." At that point, the grain was either stored or transported to Washington’s gristmill for processing into flour.

The real innovation of Washington's 16-sided barn was the way it combined and automated several steps.

Before, beating the straw to break out the grain, separating the straw from the grain, and hauling the grain to storage were separate steps.

In the 16-sided barn, everything happens at once. It also provides protection from the elements and greatly improves the efficiency of the process, cutting Washington’s losses in half.

Reconstructing the Barn

The barn was reconstructed in 1996 in accordance with the original plans and specifications that Washington sent to his carpenter.

The original barn was built in 1792 on Mount Vernon’s Dogue Run Farm by enslaved craftsmen. The barn was the center of a complex that included two corn houses and two stables housing approximately 20 animals who worked in the barn.

Visit the Farm

Wheat-Treading Demonstrations

Visit Mount Vernon to witness the treading process inside Washington's innovative 16-sided barn.

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