Native to:
Assam,
Burundi,
Cameroon,
China North-Central,
China South-Central,
China Southeast,
East Himalaya,
India,
Kenya,
Myanmar,
Nepal,
Pakistan,
Rwanda,
Sudan,
Tanzania,
Thailand,
Tibet,
Uganda,
Vietnam,
West Himalaya,
Zaïre
Introduced into:
Afghanistan,
Alabama,
Alaska,
Albania,
Alberta,
Altay,
Amur,
Arizona,
Austria,
Bahamas,
Baleares,
Baltic States,
Bangladesh,
Belarus,
Belgium,
Bermuda,
Bolivia,
Botswana,
Bulgaria,
Buryatiya,
California,
Cape Provinces,
Central European Rus,
Chita,
Colorado,
Connecticut,
Corse,
Costa Rica,
Czechoslovakia,
Delaware,
Denmark,
District of Columbia,
East European Russia,
Ethiopia,
Finland,
Florida,
France,
Free State,
Georgia,
Germany,
Great Britain,
Hungary,
Iceland,
Idaho,
Illinois,
Indiana,
Inner Mongolia,
Iowa,
Iraq,
Irkutsk,
Italy,
Jamaica,
Japan,
Kamchatka,
Kansas,
Kazakhstan,
Kentucky,
Khabarovsk,
Kirgizstan,
Korea,
Krasnoyarsk,
Krym,
KwaZulu-Natal,
Louisiana,
Magadan,
Maine,
Manchuria,
Manitoba,
Maryland,
Massachusetts,
Michigan,
Minnesota,
Missouri,
Mongolia,
Montana,
Mozambique,
Nebraska,
Netherlands,
New Brunswick,
New Hampshire,
New Jersey,
New Mexico,
New York,
New Zealand North,
New Zealand South,
Newfoundland,
North Carolina,
North Caucasus,
North Dakota,
North European Russi,
Northern Provinces,
Northwest European R,
Norway,
Nova Scotia,
Ohio,
Oklahoma,
Ontario,
Oregon,
Pennsylvania,
Poland,
Portugal,
Primorye,
Prince Edward I.,
Qinghai,
Québec,
Rhode I.,
Romania,
Sakhalin,
Sardegna,
Saskatchewan,
Sicilia,
South Carolina,
South Dakota,
South European Russi,
Spain,
Sweden,
Switzerland,
Tadzhikistan,
Tennessee,
Texas,
Transcaucasus,
Turkey,
Tuva,
Ukraine,
Uzbekistan,
Vermont,
Virginia,
Washington,
West Siberia,
West Virginia,
Wisconsin,
Wyoming,
Xinjiang,
Yakutskiya,
Yugoslavia,
Yukon,
Zambia,
Zimbabwe