Filbert Weevil

Filbert Weevils, also known as acorn weevils or nut weevils, efficiently use acorns. As larvae, acorns are food, and as adults, acorns provide a chambered nursery. After mating, the adult female weevil drills a tiny hole into a green acorn to deposit her eggs, which then hatch into creamy white legless grubs. In the fall after the acorns fall to the earth, the grubs bore holes through the shells from the inside to escape and burrow into the soil. After pupating for 1-2 years, an adult emerges from the ground in spring.

  • There is only one generation a year
  • The adult acorn weevil does not sting or bite.
  • The adult acorn weevil does not carry or transmit any diseases.
  • The larvae is a legless grub (cylindrical in shape with brown heads) tapering toward both ends.
  • An adult acorn weevil is a brown beetle with an elongated snout, known as a ‘rostrum’ saw-like teeth on the end. The rostrum of females is longer than those of males.


National Geographic Video Acorn Weevil