Crops Affected: Filberts/hazelnuts, pomegranates, acorns

States Affected: CA, OR, WA

Life Cycle: Filbert worms overwinter as larvae (a stage called prepupae) within silken cocoons under leaves, debris, in tree cracks and crevices, and in the soil. Larvae pupate in spring, emerging as adults in late spring or early summer. There are one or two generations per year, with second-generation adults, if present, appearing in the fall. Adult females lay single eggs on nuts, which hatch in 8 to 11 days. The larvae grow inside the hull, eventually chewing an exit hole in fallen nuts. They then relocate to organic litter or topsoil to become prepupae for the winter.

Damage: Infested nuts are not edible. Severe infestations can lead to significant crop loss.

Season to Trap: April to October

How To Use: Hang trap with lure inside at shoulder height near at risk or affected crops. Replace lures every 30 days through the season, and replace traps when 70% saturated. Adult males are attracted to the pheromones in the lure and the color of the traps in this kit. Once they land on the sticky trap, they become ensnared, never to mate or lay eggs again.

Additional IPM Solutions: Avoid practices that destroy or disrupt native beneficial insects. Use B.t. and spinosad sprays strategically to target eggs and wandering larvae before they enter nuts. Decrease the insect population by collecting and disposing of fallen nuts in covered containers. Choose resistant cultivars. Minimize pest loads by flailing or removing the first harvest. Manage nearby oak trees that may serve as a refuge for the pests.