The redbanded leafroller has three generations a year in New Jersey. It overwinters as pupa in cocoons in the soil surface or in the leaf litter. Eggs masses are laid on the leaves. Larvae are green with pale green heads and green thoracic shield. The obliquebanded leafroller completes two generations each year. It overwinters as a second or third instar larva on branches or near the crown region. Obliquebanded leafroller larvae are robust and green with brownish black heads and light black thoracic shields. Larvae of the obliquebanded leafroller are larger than redbanded leafroller larvae.
Larvae of both leafrollers construct shelters by webbing leaves and flowers together and feed while inside the shelter. In the second generation, larvae construct feeding tunnels by webbing leaves and fruit clusters together. Fruit clusters may become wet and moldy and can be ruined by a single worm.
Scouting and Control
Pheromone traps are used to monitor adult (male) leafroller flight activity; however, these numbers are not used for determining control actions because high trap captures do not usually mean that treatment is necessary. Instead, monitor for larvae on flowers and leaf clusters using beating tray sampling or visual inspection. Insecticide treatment for leafroller, spanworm, and gypsy moth (combined threshold) is recommended when larval numbers are more than 1 larva per 100 flower and leaf clusters. If larval populations are above threshold and application is needed during bee activity, insect growth regulators (IGRs) (Confirm or Intrepid), or Bt products should be applied for control.