Raspberry: Loopers

categories: Raspberry Raspberry Insects Small Fruits

last review date: 2025-11-13 03:57

Biology

Loopers are green caterpillar up to about 1 1⁄2″ in length. They may have pale or dark stripes along the body. They are distinguished by their characteristic looping or “measuring-worm” movement.

Loopers feed on leaves of many plants, chewing holes in the leaves or feeding along leaf margins. The adult of the alfalfa looper, a species common on raspberry, is a mottled brown moth with silver markings.

Wingspan is approximately 1 1⁄2″. The primary damage caused by loopers is the contamination of harvested fruit.

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 destroy any caterpillars or cocoons found on leaves.
• Natural enemies of caterpillars include predacious beetles, parasitic wasps, and birds. Avoid use of broad-spectrum insecticides when possible to conserve beneficial insects.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

• Apply to control loopers when first noticed.
• Use a spreader-sticker with liquid Bt formulations.

Approved Pesticides

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 registration number: 4-472]
• Bonide Thuricide BT Concentrate
  Active ingredient: Bacillus thuringiensis subsp. kurstaki [EPA registration number: 4-226]
• This list may not include all products registered for this use.