Truss (unit)

A truss is a tight bundle of hay or straw. It would usually be cuboid, for storage or shipping, and would either be harvested into such bundles or cut from a large rick.

Hay and straw were important commodities in the pre-industrial era. Hay was required as fodder for animals, especially horses, and straw was used for a variety of purposes including bedding. In London, there were established markets for hay at Smithfield, Whitechapel and by the village of Charing, which is still now called the Haymarket. The weight of trusses was regulated by law and statutes were passed in the reigns of William and Mary, George II and George III. The latter act of 1796 established the weights as follows:

... And be it further enacted that no hay or straw whatever shall be sold in any market or place within the cities of London or Westminster, or the weekly bills of mortality, or within thirty miles thereof, other than except in what is made up in bundles or trusses; ...

... that each and every bundle or truss of hay sold in any market or place within the cities or limits aforesaid, between the last day of August in any year and the first day of June in the succeeding year, shall contain and be of the full weight of fifty-six pounds at least; and that every bundle or truss of hay sold within the cities or limits aforesaid, between the first day of June and the last day of August in any year, being new hay, of the summer's growth of that year, shall be and contain the full weight of sixty pounds, and being old hay of any former year's growth, the weight of fifty-six pounds, as aforesaid; and that each and every bundle or truss of straw sold within the cities or limits aforesaid, shall contain and be of the full weight of thirty-six pounds; and that every load of hay or straw shall contain thirty-six bundles or trusses; ...

...that the pair of bands with which any bundle or truss of hay shall be bound shall not exceed the weight of five pounds, ...

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