Acorn weevil

The acorn weevil (Curculio villosus) is a beetle belonging to the order Coleoptera and the family Curculionidae. It is a well-known pest that specifically targets oak trees, playing a significant role in the forest ecosystem by impacting the regeneration of oak populations.

The primary host plants for this pest are various species of oak (Quercus). While they occasionally feed on the buds and young foliage of other trees like beech, hornbeam, or hazel, the acorn is the essential resource for the development of their offspring.

The life cycle of the acorn weevil is closely tied to the host's fructification. Adult beetles emerge in spring, feed on developing foliage, and mate. Females use their long snouts to drill into young acorns, depositing a single egg inside. The larva then develops within the acorn, consuming the nutmeat, before boring an exit hole to pupate in the soil.

The damage caused by these insects is primarily economic and ecological. By destroying the contents of the acorns, they significantly reduce the viability of seeds, making it difficult for forests to regenerate naturally. High infestation rates can lead to nearly total loss of the acorn crop in localized areas.

Integrated pest management strategies are recommended to mitigate damage. Essential practices include:

• Collecting and destroying infested acorns before larvae emerge.
• Cultivating the soil beneath infested trees to disrupt the pupation sites.
• Applying specific insecticides in nurseries when adults are active in the spring.
• Monitoring the beetle population during the flowering and fruiting stages of the oak.