Native to:
Afghanistan,
Alabama,
Alaska,
Albania,
Alberta,
Aleutian Is.,
Algeria,
Altay,
Amur,
Arizona,
Arkansas,
Assam,
Austria,
Baltic States,
Bangladesh,
Belarus,
Belgium,
British Columbia,
Bulgaria,
Buryatiya,
California,
Cambodia,
Central European Rus,
China North-Central,
China South-Central,
China Southeast,
Chita,
Colorado,
Connecticut,
Czechoslovakia,
Delaware,
Denmark,
District of Columbia,
East European Russia,
East Himalaya,
Finland,
France,
Georgia,
Germany,
Great Britain,
Greece,
Hungary,
Idaho,
Illinois,
India,
Indiana,
Inner Mongolia,
Iowa,
Iran,
Iraq,
Ireland,
Irkutsk,
Italy,
Japan,
Kamchatka,
Kansas,
Kazakhstan,
Kentucky,
Khabarovsk,
Korea,
Krasnoyarsk,
Krym,
Kuril Is.,
Laos,
Lebanon-Syria,
Louisiana,
Magadan,
Maine,
Manchuria,
Manitoba,
Maryland,
Massachusetts,
Michigan,
Minnesota,
Mississippi,
Missouri,
Mongolia,
Montana,
Myanmar,
Nebraska,
Nepal,
Netherlands,
Nevada,
New Brunswick,
New Hampshire,
New Jersey,
New Mexico,
New York,
Newfoundland,
North Carolina,
North Caucasus,
North Dakota,
Northwest European R,
Northwest Territorie,
Norway,
Nova Scotia,
Ohio,
Oklahoma,
Ontario,
Oregon,
Pakistan,
Pennsylvania,
Poland,
Portugal,
Primorye,
Prince Edward I.,
Qinghai,
Québec,
Rhode I.,
Romania,
Sakhalin,
Saskatchewan,
South Carolina,
South Dakota,
South European Russi,
Spain,
Sweden,
Switzerland,
Taiwan,
Tennessee,
Thailand,
Tibet,
Transcaucasus,
Tunisia,
Turkey,
Turkey-in-Europe,
Tuva,
Ukraine,
Utah,
Vermont,
Vietnam,
Virginia,
Washington,
West Himalaya,
West Siberia,
West Virginia,
Wisconsin,
Wyoming,
Yakutskiya,
Yugoslavia,
Yukon