Pest profile

Vegetable Weevil

Listroderes difficilis (also listed as L. costirostris) · Coleoptera: Curculionidae[2]

Vegetable weevils feed at night on seedlings and roots and hide by day; since adults can't fly, damage tends to be spotty.[1]

Vegetable weevil, a small brown-gray snout beetle with a pale V-shaped mark near the wing tips, on a flat surface
Vegetable weevil, a small brown-gray snout beetle with a pale V-shaped mark near the wing tips, on a flat surface. (c) Michelle W. （鍾偉瑋）, some rights reserved (CC BY) — via iNaturalist, CC BY 4.0

How to identify it

  • Adults are small brown or gray snout beetles about 3/8 inch long with a V-shaped spot at the wing tips; they can't fly.[1]
  • Larvae are green, legless grubs about 3/8 inch long when grown.[1]

Look-alikes

Look-alikeHow to tell them apart
Black vine weevilUC IPM names the black vine weevil as California's most common pest weevil; the vegetable weevil is a separate species with a V-shaped wing mark.[1]

Where it lives

UC IPM lists it among the important pest weevils of California gardens.[1]

US map: public records from 19 states since 1990 (GBIF).

Biology and life cycle

It has one generation a year, but adults may live two years or more.[1]

Adults and larvae are most active at night and hard to find by day.[1]

Damage and signs

  • Both stages feed on buds, foliage and roots of potatoes, tomatoes, carrots, lettuce and other vegetables.[1]
  • Young plants may be cut off at ground level or stripped of leaves.[1]

Health risk

It feeds on plants; UC IPM mentions no risk to people.[1]

Control

Keep them out

Protect young plants with fabric covers, and use sticky barriers to keep weevils from walking into new areas.[1]

Traps and physical control

Pick off weevils at night, and destroy infested rows to stop local spread.[1]

Pesticides

Pyrethrin or azadirachtin mixtures may give some control; spot treatments may be enough.[1]

Common questions

What's cutting my seedlings off at night?
Vegetable weevils feed at night and can cut young plants at ground level.[1]
Can vegetable weevils fly?
No, so infestations spread slowly and damage is often patchy.[1]

Sources

  1. University of California Statewide IPM Program, “Vegetable Weevil (Pests in Gardens and Landscapes).” ipm.ucanr.edu/PMG/GARDEN/VEGES/PESTS/vegeweevil.html (accessed 2026-10-06)
  2. iNaturalist, “Listroderes difficilis taxon page (order and family).” www.inaturalist.org/taxa/391814 (accessed 2026-10-06)

Updated 2026-10-14. Built from sourced records. Spot an error? Tell us.