Pest description and crop damage The small greenish larvae mine leaves. Later, they feed on terminal leaves and bore into developing flowers and inside the stems. Adult is grayish brown with narrow plumed wings and a 0.5 inch wingspread.
Pest biology and life cycle Adults are considered weak fliers. They tend to remain on or near the host plant. They are most active during early evening. Single eggs are usually deposited on new forming flower heads or underside of leaves near new growth. It takes 2-4 weeks for the eggs to hatch and the new larvae burrow into stems, flower buds, and seed heads where the larvae feed and develop for about 3-5 weeks. Caterpillars pupate while hanging from plants. Adult is the overwintering stage.