The larvae feed on "Betula" and "Corylus avellana". It is a particular problem on "Corylus avellana", which is farmed commercially. It is surrounded by woods, mostly of hazel trees ("Corylus avellana"). Ash ("Fraxinus excelsior") and Hazel ("Corylus avellana"). A selection with twisted branches has been propagated horticulturally as "Corylus avellana" 'Contorta'. The larvae feed on "Corylus avellana", "Corylus colurna" and "Corylus maxima". The larvae feed on "Malus" and "Corylus" species, including "Corylus avellana". The larvae feed on "Corylus" (including "Corylus avellana"), "Ulmus" and "Prunus persica" species. The larvae feed on "Corylus avellana", oak, European beech, "Carpinus betulus", birch and "Acer campestre". The larvae feed on hazel ("Corylus avellana") and sometimes hornbeam ("Carpinus betulus"). This article is a list of diseases of hazelnut ("Corylus avellana" & "Corylus" spp.).