Currant, Gooseberry: Imported currantworm
Photo by: K. Grey
Biology
The imported currantworm is the larva of a sawfly. The adult sawfly is black and yellow and is about 1⁄3″ in length. The female lays eggs on the underside of leaves, near the midrib. The larvae feed along leaf margins, sometimes causing severe defoliation. The larvae are whitish at first, but become greenish with distinctive black spots and heads as they reach maturity. Mature larvae are about 1⁄2″ long.
They pupate in the soil beneath the host plants. A second generation may occur, appearing around June or July. Larvae overwinter in cocoons in the soil. Adults typically emerge in early spring.
Management Options
See "Using Integrated Pest Management (IPM) in the Landscape" for successful problem management techniques.
Non-chemical Management
Select non-chemical management options as your first choice!
- Hand-pick and kill larvae when noticed.
- Floating row cover may be useful.
Chemical Management
IMPORTANT: Always read and follow label directions when working with pesticides.
For more information on using pesticides visit :
- Monitor plants in April for small holes in the center of leaves from larval feeding.
- Do not make an application if there is no evidence of larvae or damage.
Approved Pesticides
If you choose to use a pesticide, some examples of products that are legal in Washington are listed below. Some products are labeled for just INDOOR or just OUTDOOR use, or may allow both uses. Be sure to choose a product appropriate for your situation. Always read and follow all label directions.
Additional Image
Photo by: B.M. Johnson
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Evidence of noncompliance may be reported through your local Extension office.