BeneficialCabbage looper
Paper wasps for cabbage looper
Polistes spp. · wild predator (stings)
Against cabbage looper
In Iowa State trials published in 2024, native paper wasps removed every cabbage looper placed on broccoli in a hoop house, and on kale, by the second day, Polistes fuscatus took over 80% of the looper larvae within three hours of their being put out. Wasps carry caterpillars back to feed their larvae. The trials were short, so keep Bt for young loopers and count nearby nests as extra help.
RateWild — tolerate nests away from doors and paths
TimingSpring through late summer, while nests are raising young
macro · paper wasps on cabbage looper
The pestCabbage looperTrichoplusia niRagged holes between leaf veins; frass in the headsFull pest profile →Before you act
Slender wasps with a thin waist and dangling legs, nesting in open, umbrella-shaped paper combs under eaves. They hunt caterpillars to feed their larvae, and they can sting. A nest away from doors and paths is usually worth leaving. How to recognise it, what it is confused with and how to keep it around are on the full Paper wasps profile.
Other controls for cabbage looper
- Bacillus thuringiensis kurstakiMicrobial insecticide · Label rate — Thuricide 2–4 tsp per gallon for cabbage looper
- Trichogramma spp.Egg parasitoid wasp · 25,000–100,000 /acre twice a week, light to heavy pressure (Rincon-Vitova, cole crops); 1–2 /ft² in gardens
- Tachinid fliesWild parasitoid · Wild — keep nectar plants near the crop, no broad-spectrum sprays