A hybrid between our native American hazelnut (Corylus americana) and the European filbert (C. avellana). American hazelnut provides disease resistance while the filbert, selected for productivity and large nuts for hundreds, perhaps thousands of years brings heavy crops of good-sized nuts to the cross. Hazelnuts grow in full shade but you won’t get much nut production; a little light shade though won’t diminish productivity. Plant more than one shrub for cross-pollination. Protect from squirrels. For more info on hazelnuts and sustainable agriculture, search for Hybrid Hazelnut Consortium on the web.