Root Weevils

Otiorhynchus spp.

Lilac root weevil

Lilac root weevil (Entomart, Wikimedia Commons)

Root weevil

Strawberry root weevil size comparison (Whitney Cranshaw, Colorado State University,

root weevil

Root weevil damage to leaves (Whitney Cranshaw, Colorado State University,



  • up to 1/2 inch long; legless white grub with a brown head capsule


  • 1/4 - 1/2 inch long
  • shiny black to shiny brownish black
  • blunt snout

Nesting Habits

  • larvae develop in soil at the base of host plants
  • adults spend the day at the base of host plants in litter


  • larvae: roots of woody shrubs, especially lilac
  • adults: leaf margins of many plants


  • adults are common nuisance invaders of homes during late summer and fall
  • can damage leaves and roots of ornamental plants

IPM Recommendations

  • Use a vacuum and/or sticky traps to collect weevils indoors.
  • Seal cracks, crevices, windows and other areas where weevils can enter.
  • Larvae and feeding adults can be managed outdoors with an appropriately labeled, soil-applied insecticide.