Region
United States
2
California
1
Canadian Valley (N.M.)
1
Canadian Valley (Okla.)
1
Canadian Valley (Tex.)
1
Chapel Hill (N.C.)
1
Cimarron Valley
1
Cincinnati (Ohio)
1
Colorado
1
Durham (N.C.)
1
Houston (Tex.)
1
Illinois
1
Massachusetts
1
Missouri River Valley
1
Montana
1
New Mexico
1
New York (N.Y.)
1
New York (State)
1
Ohio
1
Potomac River Valley
1
Raleigh (N.C.)
1
Sacramento Valley (Calif.)
1
South Dakota
1