Native to:
Japan,
Korea,
Kuril Is.,
Sakhalin
Introduced into:
Austria,
Baltic States,
Belgium,
British Columbia,
Bulgaria,
California,
Central European Rus,
Connecticut,
Czechoslovakia,
Delaware,
Denmark,
Finland,
France,
Germany,
Great Britain,
Idaho,
Illinois,
Ireland,
Kentucky,
KwaZulu-Natal,
Louisiana,
Maine,
Maryland,
Massachusetts,
Michigan,
Minnesota,
Montana,
Netherlands,
New Brunswick,
New Hampshire,
New Jersey,
New York,
New Zealand North,
New Zealand South,
Newfoundland,
North Carolina,
North Caucasus,
Norway,
Nova Scotia,
Ohio,
Ontario,
Oregon,
Pennsylvania,
Poland,
Primorye,
Prince Edward I.,
Québec,
Rhode I.,
Romania,
Sweden,
Tennessee,
Ukraine,
Vermont,
Virginia,
Washington,
West Virginia,
Wisconsin