Straight-snouted acorn weevil

Systematic position: The straight-snouted acorn weevil (Curculio rectus) belongs to the order Coleoptera and the family Curculionidae. It is a specialized insect known for its intricate ecological association with oak trees, specifically targeting the reproductive structures of the genus Quercus.

Host plants: The primary hosts for this species are various species of oak. While adult beetles feed on the leaves and tender bark, the larvae are exclusively internal feeders, developing within the acorns, which makes the pest particularly problematic for forestry and oak nursery management.

Biology and life cycle: The life cycle typically spans one to two years depending on environmental conditions. In the spring, adult weevils emerge and mate. Using their elongated rostrum, females drill holes into developing acorns to oviposit. The larva feeds inside the nut, consuming the embryo and cotyledons, before exiting the acorn to pupate in the soil.

Damage and economic impact: The damage caused by Curculio rectus is significant because it directly destroys the acorn embryo, rendering the seed non-viable. In severe infestations, the vast majority of an acorn crop can be destroyed, which drastically inhibits natural regeneration and poses a severe challenge for commercial oak seed collection.

• Foliar insecticide applications targeting adults during the peak emergence period.
• Frequent collection and disposal of fallen acorns to reduce larval populations.
• Mechanical cultivation of soil under the canopy to disrupt the pupation stage.
• Monitoring of weevil activity using pheromone traps where available.