Juglans regia

Juglans regia is a large deciduous tree that was introduced from Asia already more than two Millenia ago and is widespread in Southern and Central Europe. It is fairly light-demanding and can reach diameters of >100 cm. Widely cultivated because of its nuts Juglans regia also has one of the most valuable woods in Europe. It is chocolate brown, strong and easy to work with. It is used for furniture, veneer, and turned objects, among others.
The walnut tree has been introduced to multiple regions in central and western Europe since many centuries and has become naturalized there in forests widely. Still, the number of recorded herbivores remains rather low, though substantially higher than for the horse chestnut with a similar geographical origin and cultivation history. All herbivore species reported from Europe are polyphagous opportunistic feeders that just occasionally utilize walnut as a minor food resource.
References: ^1,2,3,6,8