7 C.F.R. § 1033.2
The marketing area means all territory within the bounds of the following states and political subdivisions, including all piers, docks, and wharves connected therewith and all craft moored thereat, and all territory occupied by government (municipal, State, or Federal) reservations, installations, institutions, or other similar establishments if any part thereof is within any of the listed states or political subdivisions:
Indiana Counties Adams, Allen, Bartholomew, Benton, Blackford, Boone, Brown, Carroll, Cass, Clay, Clinton, Dearborn, Decatur, De Kalb, Delaware, Elkhart, Fayette, Fountain, Franklin, Fulton, Grant, Hamilton, Hancock, Hendricks, Henry, Howard, Huntington, Jackson, Jasper, Jay, Jefferson, Jennings, Johnson, Kosciusko, Lagrange, Lake, La Porte, Lawrence, Madison, Marion, Marshall, Miami, Monroe, Montgomery, Morgan, Newton, Noble, Ohio, Owen, Parke, Porter, Pulaski, Putnam, Randolph, Ripley, Rush, Shelby, St. Joseph, Starke, Steuben, Switzerland, Tippecanoe, Tipton, Union, Vermillion, Vigo, Wabash, Warren, Wayne, Wells, White, and Whitley. Kentucky Counties Boone, Boyd, Bracken, Campbell, Floyd, Grant, Greenup, Harrison, Johnson, Kenton, Lawrence, Lewis, Magoffin, Martin, Mason, Pendleton, Pike, and Robertson. Michigan Counties All counties except Delta, Dickinson, Gogebic, Iron, Menominee, and Ontonagon. Ohio The townships of Woodville and Madison in Sandusky County and all other counties in Ohio except Erie, Huron, and Ottawa. Pennsylvania Counties Allegheny, Armstrong, Beaver, Butler, Crawford, Erie, Fayette, Greene, Lawrence, Mercer, Venango, and Washington. In Clarion County only the townships of Ashland, Beaver, Licking, Madison, Perry, Piney, Richland, Salem, and Toby. All of Westmoreland County except the townships of Cook, Donegal, Fairfield, Ligonier, and St. Clair, and the boroughs of Bolivar, Donegal, Ligonier, New Florence, and Seward. West Virginia Counties Barbour, Boone, Brooke, Cabell, Calhoun, Doddridge, Fayette, Gilmer, Hancock, Harrison, Jackson, Kanawha, Lewis, Lincoln, Logan, Marion, Marshall, Mason, Mingo, Monongalia, Ohio, Pleasants, Preston, Putnam, Raleigh, Randolph, Ritchie, Roane, Taylor, Tucker, Tyler, Upshur, Wayne, Wetzel, Wirt, Wood, and Wyoming.