There are hazelnuts indigenous to both Europe and North America--but the two nuts are different from each other..that is, if my memory is serving me well right now. I will look this up..

Same with walnuts--we have the American and the English walnut trees, both of which grow here in the USA. But I don't know whether the English walnut was introduced into the British Isles or was always native there. If always native there, then it was a foreign indigenous walnut tree--odd nomenclature when you think about it.