Pieris (Andromeda): Black vine weevil
categories: Ornamentals Pieris (Andromeda) Pieris (Andromeda) Insects Shrubs
revision date: 2023-04-04 12:00
Photo by: A.L. Antonelli
Biology
Characteristic damage by black vine weevils includes irregular, ragged notching of leaf margins by adults and minor to severe root and bark damage by larvae. The adult is a gray to black beetle about 2/5″ long which feeds at night. The larvae feed below ground on roots or just beneath the soil surface on the bark at the crown of the plant. Bark feeding can result in girdling and plant death.
Management Options
Use Integrated Pest Management (IPM) for successful plant problem management.
Non-chemical Management
Select non-chemical management options as your first choice!
- Hand-pick and kill night-feeding adults.
- Apply beneficial nematodes to kill larvae. The nematodes are most effective when applied as a soil drench in moist soils over 52 F. (late summer to early fall in western Washington). Read and follow all label directions carefully.
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
- Apply when first signs of notching on new leaves are noticed.
- Monthly applications may be needed if infestation is heavy.
- Cease when first hard frost occurs in late fall/early winter.
- Night applications are more effective. Beneficial nematodes can be ordered from certain nurseries. They can be applied to control the larval stage if soil temperatures are warmer than 52 F.
- Do not apply nematodes in direct sunlight and be sure soil is saturated with water before application.
Approved Pesticides
Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.