Nut weevil

Systematic position. Curculio pellitus belongs to the order Coleoptera and the family Curculionidae. This species is widely recognized as a specialized pest that maintains a tight ecological relationship with Quercus (oak) and Corylus (hazel) species, significantly affecting commercial nut orchards across its distribution range.

Host plants and damage. The pest primarily targets hazelnut kernels and oak acorns. Adult weevils feed on young foliage and developing buds; however, the larvae are the most destructive stage. They burrow into the developing nut and consume the kernel, leaving behind debris and making the fruit completely unmarketable.

Biology and life cycle. The adult weevils emerge in the spring, synchronized with the development of the host plant's fruit. The female uses her elongated rostrum to drill a hole into the young nut and deposit an egg inside. After hatching, the larva develops within the nut for about a month before exiting and dropping to the soil to pupate.

Damage patterns. Infested nuts often exhibit premature abscission and fall to the ground early in the season. A hallmark of the damage is a small, circular exit hole created by the mature larva. These holes not only indicate infestation but also expose the remaining nut tissue to fungal pathogens, further reducing the quality of the harvest.

Protection measures. Effective control involves monitoring beetle populations using traps during the spring emergence. Cultural practices, such as clearing fallen nuts promptly to prevent larvae from burrowing into the soil, are essential. Chemical control, applied at the right phenological stage of the hazelnut, is often necessary to minimize crop loss.