Salix viminalis
The adult insect (imago) over-winters in dry dark places, such as hollow trees or out buildings. In late February or early March the butterflies emerge and mate. The females lay their pale green eggs (ova) in a continuous band around the upper twigs of elm ("Ulmus" spp.), sallow ("Salix caprea" and "Salix viminalis"), pear ("Pyrus" spp.), "Malus", "Sorbus", "Crataegus", "Populus", and "Prunus" spp. trees.