William J. Conroy Of Aylmer, Quebec, Received Patent No. 465,127 On The First Field Hay Chopper On 15 December, 1891. Its Sickle Cut The Crop, Which Was Elevated Directly Into A Cylindrical Curved-Bar Cutterhead. It Was Not Commercially Successful, But It Recognized The Need.

Professor Floyd Waldo Duffee, Agricultural Engineering Department, University Of Wisconsin, Built And Field Tested A Silo Filler With An Attached Hay Loader In 1926. He Presented The Specifications Of A Complete Unified Harvester To The National Asabe Meeting In 1927.

The J. I. Case Company Built A Field Machine For Duffee, Which He Tested And Improved Until 1930.

Mr. Erwin W. Saiberlich, Chief Engineer Of The Fox River Tractor Co., Appleton, Wisconsin, Had Also Put Together Such A Machine. At Duffee's Urging Saiberlich Built His First Harvester In 1931, Which He Improved And Sold In 1932. He Redesigned The Machine During The Great Depression And Fox Began Selling It In 1936. His Design Was So Fundamentally Correct In Principle That All The Machines Built 50 Years Later Were Still Very Similar. More Than 600,000 Such Harvesters Had Been Built By 1986. This Development, Which Significantly Reduced The Cost And Labor To Harvest, Store And Feed Forage, Is Hereby Dedicated By The American Society Of Agricultural Engineers 1988