Key Features
- Notched leaf margin
- Small 1/8 inch grey weevils
Symptoms
Adult weevils feed on leaf margins in daytime causing irregular notches. Notches are much smaller than those caused by black vine weevil. Larvae feed on roots of host plants in the soil. Feeds on a wide range of trees, shrubs. Rarely causing significant damage to the health of large trees. New plantings can be damaged if located at a site with large numbers of weevils.
Biology
Weevils winter as adults, in leaf litter, and as pupae and larvae in the soil. Adults become active in summer when weather warms. A new generation of adults emerges in mid summer. Adults continue to feed until frost.
Management Recommendations
If significant notching is present on new planting adults can be killed with a foliar insecticides. Damage is mostly aesthetic in nature so control is rarely warranted outside of a nursery production situation. Soil drenches of a systemic insecticide (imidacloprid, dinotefuran, and clothianidin) in mid-August will kill young grubs in the soil. To protect bees, do not apply foliar insecticides when bees are flying to flowers and avoid using soil insecticides like imidacloprid, dinotefuran and clothianidin on plants prior to or during flower production.
Effective Pesticides
Active Ingredients include: Acetamiprid, Bifenthrin, Carbaryl, Clothianidin, Dinotefuran, Imidacloprid
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