By Scout Nelson
Banded sunflower moths are active during the growing season and can seriously reduce sunflower yields if they are not managed at the right time. The caterpillars feed-on developing sunflower florets and seeds, reducing pollination and lowering the number of healthy seeds that mature before harvest. Regular field scouting helps growers detect the pest early and make better management decisions.
Adam Varenhorst, Associate Professor & SDSU Extension Field Crop Entomologist, along with Philip Rozeboom, Patrick Wagner, and Brad McManus, highlighted that early scouting is the best way to protect sunflower fields from banded sunflower moth damage. Monitoring plants before caterpillars begin feeding gives producers more time to decide if treatment is needed.
Adult banded sunflower moths are small cream-colored insects with a dark brown band across their wings. They appear from late June through July and lay tiny white eggs on sunflower bracts during the late bud stage.
About one week later, caterpillars hatch and begin feeding on the sunflower head. Young caterpillars are white or cream colored before changing to pink, red, and finally green as they mature.
Growers should begin scouting when most sunflower plants reach the R3 growth stage, which is the midsized bud stage. Fields can be checked by examining sunflower bracts for eggs or by looking for adult moths.
A hand lens may help identify the tiny eggs. Adult moths should be counted by inspecting plants at several locations throughout the field instead of only near field edges.
Economic injury level tools help determine if treatment is needed by considering treatment cost, crop value, and the number of eggs or moths present. These tools help growers avoid unnecessary insecticide applications while protecting crop yield when pest numbers reach damaging levels.
After feeding is complete, mature caterpillars fall to the soil, where they pupate and survive the winter before emerging the following season. This yearly life cycle makes regular scouting an important part of sunflower management every summer.
Using timely scouting, proper identification, and recommended management practices helps protect sunflower yield, oil content, and seed quality.
FAQs
- What damage does the banded sunflower moth cause?
Its caterpillars feed-on sunflower florets and developing seeds, reducing yield and oil content.
- When should growers begin scouting?
Scouting should begin when most sunflower plants reach the R3 midsized bud stage.
- Where do moths lay their eggs?
Female moths lay tiny white eggs on the outer bracts of sunflower heads.
- How can growers scout for banded sunflower moths?
Growers can inspect sunflower bracts for eggs or count adult moths on plants throughout the field.
- Why is early scouting important?
Early scouting allows growers to make timely management decisions before caterpillars begin causing significant crop damage.
Photo Credit: South Dakota State University
Categories: South Dakota, Crops