Root Weevils

    Root Weevils

    Root weevil damage to peach leaves Root weevil damage to peach leaves.
     Adult root weevil. Adult root weevil.

    HOSTS

    • All fruit trees, especially peach
    • Strawberry

    DESCRIPTION

    The adults are rounded beetles with a hard exterior and a pronounced “snout”. Adults chew half-circle notches into leaf edges causing “scalloping.” Adults are primarily active at night.

    Adults encountered during the day will quickly hide or drop to the ground. Young weevils are c-shaped legless grubs that feed on roots.

     

    BIOLOGY

    Root weevils, like the lilac root weevil or strawberry root weevil, overwinter as larvae in the ground. Adults emerge in the late spring to feed on foliage and lay eggs at the base of plants throughout the season.

    SYMPTOMS

    • Semi-circular notches at leaf edges
    • Reduced plant growth due to larval feeding on roots

    MONITORING

    Check for leaf damage (notching at edges) in late spring.

    GENERAL MANAGEMENT

    The best timing to apply a treatment is in the spring and early summer when leaf-notching injury first appears, and again in the late summer to early fall to target larvae before winter. Early season treatment targets adults (carbaryl) while late season treatments target larvae in the soil. Larvae can be killed by nematodes or beneficial fungi applied to the soil at the base of plants.

     


    Precautionary Statement: Utah State University and its employees are not responsible for the use, misuse, or damage caused by application or misapplication of products or information mentioned in this document. All pesticides are labeled with ingredients, instructions, and risks, and not all are registered for edible crops. “Restricted use” pesticides may only be applied by a licensed applicator. The pesticide applicator is legally responsible for proper use. USU makes no endorsement of the products listed in this publication.