- Native parasitic wasps and flies
- Tachinid fly
- Assassin bug
- Ladybird beetle
- Weaver ant
the crop regularly to look for the larva. A larva is usually found resting along the main leaf vein, on the center of the plant, and on the fresh green piles of frass
. A closer look is necessary because the larva camouflages
with the leaf.
The general recommendation for when to implement a control measure is when there is 1 larva or a 1 new feeding hole in every 10 plants during the early head formation (Griffin, 1999).
The recommended sample sizes are: 20 plants for eggs; 30 plants for young larvae; 40 plants for mid-age larvae; 50 plants for large larvae; and 70 plants for pupae (Capinera, 2000).
Cultural and management practices
- Practice crop rotation with non-cruciferous crops.
- Plow-under all plant resides after harvest. This will expose larvae and pupa to predators and sunlight.