WSU Extension

Hortsense

Currant, Gooseberry : Imported currantworm
(revision date: 3/22/2021)


Use Integrated Pest Management (IPM) for successful plant problem management.

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

Non-Chemical Management
  • Hand-pick and kill larvae when noticed.
  • Floating row cover may be useful.
Select non-chemical management options as your first choice!

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.
  • Bonide Captain Jack's Deadbug Brew R-T-U [Organic]
    Active ingredient: spinosad (spinosyn A+D)  |  EPA reg no: 4-472
  • Safer Brand Insect Killing Soap Conc II [Organic]
    Active ingredient: potassium salts of fatty acid  |  EPA reg no: 42697-60
  • This list may not include all products registered for this use.
Images
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Caption: Imported currantworm
Photo by: K. Grey
Caption: Imported currantworm color variation Imported currantworm color variation
Photo by: B.M. Johnson