Broccoli, Cole crops: Loopers

Biology

Loopers are typically green caterpillars up to about 1 1⁄2″ long. 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 moth of the cabbage looper, one common species, is gray-brown and has a silvery spot on each forewing. Cocoons of this species can often be found attached by one side on leaves. The alfalfa looper moth is mottled brown with silver markings. Both species have a wingspan of about 1 1⁄2″. Eggs are laid on leaves of host plants.

Management Options

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

Non-chemical Management

Select non-chemical management options as your first choice!

• Cover crops with floating row covers or screen cages to prevent egg-laying by adults.
• 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 at 5 to 7 day-intervals starting when worms or damage is first observed (use 7-day intervals for Bonide Thuricide and Safer Brand Caterpillar Killer).
• Apply Bt only when caterpillars are feeding.
• 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]
• Bug Buster-O [Organic]
  Active ingredient: pyrethrins [EPA registration number: 1021-1771-54705]
• ferti-lome Dipel Dust
  Active ingredient: Bacillus thuringiensis subsp. kurstaki [EPA registration number: 7401-290]
• Safer Brand BioNEEM Multi-Purpose Insecticide and Repellent Concentrate [Organic]
  Active ingredient: azadirachtin [EPA registration number: 70051-6-42697]
• Safer Brand Caterpillar Killer for Trees, Shrubs and Vegetables Concentrate II [Organic]
  Active ingredient: Bacillus thuringiensis subsp. kurstaki [EPA registration number: 70051-106-42697]
• Garden Safe BT Worm and Caterpillar Killer
  Active ingredient: Bacillus thuringiensis subsp. kurstaki [EPA registration number: 9688-294-39609]
• This list may not include all products registered for this use.

Additional Images