European corn borer in peppers
Pepper tolerates far less corn borer than corn does, because the larvae go straight into the fruit, tunnelling in under the cap. Once inside, they are out of reach. That is why UMass uses higher Trichogramma rates in pepper than in corn. In trials across Virginia, Pennsylvania and Massachusetts, egg parasitism averaged 48.7% in T. ostriniae release plots against 1.9% in plots without releases, and fruit damage 8.7% against 27.3%. None of the suppliers on the site's Trichogramma page lists T. ostriniae, so ask which species you are buying. The wasps attack only the eggs, so the release has to match the moth flight.
At a glance
- Damage
- Tunnels in stalks and ears; holes under the pepper cap
- Type
- Chewing
- Settings
- Field, Garden
- Threshold
- Start sprays one week after trap catches reach 7 moths per week with fruit on the plants (UMass)
- Release
- Trichogramma spp.
- Rate
- 90,000–120,000 wasps per acre per release, weekly for 4 weeks from the start of the moth flight; in pepper that is the midsummer flight (UMass)
How to confirm it
Small entry holes with frass on corn stalks, tassel stems or the side of the ear, and broken tassels. In peppers, a hole under the fruit cap. Split the stalk or fruit: the larva is up to about 1 inch (2.5 cm), light brown or pinkish-grey with round dark spots on each segment and a dark head.
Identification, lifecycle, degree days and every control option are on the full European corn borer profile. Not sure it is this pest? Answer four questions about the damage.
Work it out
How many do I need?
Carries Trichogramma spp. and pepper through so nothing is re-entered. Open the calculator →