Then in the fall, the winged forms are produced. These winged forms produce the egg laying forms that create the overwintering population. Another secondary problem comes with heavy aphid infestations, that is black sooty mold. This is a secondary fungus that growers on the sweet honeydew left on the leaf surface by aphids feeding. This can reduce the photosynthetic capacity of the leaf.
Growers also report displeasure at working in orchards with sticky leaves caused by the honeydew.
The filbert leafroller is a native of Europe. It was accidentally introduced in 1915. The filbert leafroller overwinters as an egg. Those eggs hatch in late March or early April. The newly hatched larvae feed on both sides of the new leaves.