Weevil Damage on Laurels

What's a Weevil?

• Weevils are beetle-like insects with hard carapaces and wings. They are typically black to dark brown in color but may also be gray. The insects are small, usually less than 3/8-inch, and have a characteristic pointed snout. Weevils produce larvae that are larger than their parent and live primarily in the soil. The larvae feed on roots to fuel the change into pupae. The adults generally emerge in spring and begin leaf feeding, hiding in crevices and under leaves.

Foliar Damage

• The damage on leaves from weevils produces C-shaped notches on leaf edges. The curved edges of feeding sites are characteristic of weevil damage of all varieties. Weevils that feed on the leaves will not severely damage the health of a laurel unless there is a severe infestation. The damage does look unsightly on landscape plants, and a large amount of damaged leaves can indicate a significant population of the insects and a potentially large concentration of the more damaging larvae.

Other Damage

• Weevil larvae cause significant loss in plant vigor when they are found in high populations in the soil. This is due to their habit of feeding on roots. The larvae live in the soil all winter and feed until May. The roots may become girdled, which is significant to the laurel when large numbers of larvae are feeding. This impacts the plant's ability to absorb water and nutrients that, in turn, causes a reduction in plant health over time.

Controls

• Weevils come out mostly at night and can be knocked off the plant stems to reduce their population. Heavy mulching can create excess moisture, which encourages the growth of eggs and larvae, so it should be removed around affected plants. Beneficial nematodes are a natural control that can be introduced in fall while the larvae are tiny. There are also chemical sprays that can be applied two to three weeks before the adults emerge in spring. These will need to be reapplied two weeks later because adult emergence is over a period of several weeks.