Scientific Name: Trichoplusia ni (Hübner)
What Do Cabbage Loopers Look Like?
The cabbage looper is light green with white or yellow stripes when in its caterpillar stage. It grows to 1-1/2” to 2” long. As an adult moth, it is ¾” long with mottled grayish brown wings adorned with a round white mark on each.
Where Are Cabbage Loopers Found (US)?
Cabbage loopers can be found across the United States but they only overwinter in the southeast. They have been tracked traveling as far as 200+miles.
What Do Cabbage Loopers Eat?
Crops that are affected by cabbage loopers are all brassica crops including broccoli, Brussels sprouts, cabbage, cauliflower, Chinese flowering broccoli, collards, kale, kohlrabi, mustard, radish, rutabaga, turnip, and watercress. They also feed on beet, cantaloupe, celery, cucumber, dry beans, endive, escarole, lettuce, lima beans, mesclum, parsley, parsnip, pea, pepper, potato, snap beans, spinach, squash, sweet potato, tomato, and watermelon.
Vegetables aren’t the only victims of the cabbage looper. If available, they will feed on chrysanthemum, cotton, hollyhock, snapdragon, sweetpea, and tobacco.
How Do I Know If I Have Cabbage Loopers?
There are several telltale signs that Cabbage Loopers may be attacking your plants. Here’s what to look for.
Presence of Eggs. Cabbage loopers lay light yellow or green, globe shaped eggs on the underside of foliage.
Ragged holes. Cabbage loopers feed on foliage and heads leaving behind large, ragged holes.
Accumulation of sticky material. A sure sign of the presence of a cabbage looper feeding site is the accumulation of frass, which is its fecal matter.
Can I Get Rid of Cabbage Loopers Naturally?
Parasitic Insects. Several parasites are important for cabbage looper control including Trichogramma pretiosum, Hyposoter exiquae, Copidosoma truncatellum, Microplitis brassica, and Voria ruralis.
Pathogens. Bacillus thuringiensis is a bacterial pathogen that can be applied to effectively control the cabbage looper population. The virus nuclear polyhedrosis can effectively wipe out infestations.
Remove spent foliage. Immediately after harvesting your crop, destroy spent foliage to discourage potential overwintering.
Remove preferred weeds. Several weeds are highly attractive to cabbage loopers including peppergrass, shepard’s purse, and wild mustard. Keep these far away from crops.
Inspect before You Purchase. When buying plants to transplant into your garden, inspect the underside of the leaves carefully for eggs or newly hatched larvae.