In 2020, Sioux County led all Iowa counties in total corn silage production, with 919,000 tons according to the USDA’s National Agricultural Statistics Service. Lyon (579,000), Winneshiek (386,000), Dubuque (295,000) and Clay (294,000) rounded out the top five highest producing counties.
Clayton County had the highest yield with an average of 23.5 tons per acre. Sioux, Cerro Gordo and Delaware were tied for second highest yields at 22.5 tons per acre. There were 21 counties that had an average yield of 20.0 or more tons per acre.
Yields are derived from production divided by area harvested. Only published estimates were considered in rankings of counties.