Sweet corn sweet corn sweet corn..Corn Flea Beetle (Chaetocnema pulicaria)

Flea beetle numbers can be very high in Kentucky in the early spring following years with mild winter temperatures. Flea beetles are small, black, hard-bodied insects that hop or fly quickly when disturbed. They overwinter as adults and become active early in the spring. Flea beetles attack young corn plants as soon as the first true leaf appears. Flea beetles produce small feeding streaks or scarring on the leaves. During wet, cold periods in the spring when corn is growing slowly, damage from this pest can be severe. Only rarely will this actually kill plants. The real concern from flea beetles is Bacterial Wilt (Stewart’s Wilt), a bacterial disease of corn. The pathogen is carried inside the flea beetle. Young plants become infected as the beetles feed. Damage from Stewart's wilt is far more severe than leaf injury caused by the beetles. Wilt resistant sweet corn varieties should be selected to prevent losses. Foliar sprays should be applied if flea beetle damage appears serious.
Chemical control of the beetle should not be the only protection program for Stewart's wilt.

Controls
Cultural: In years following mild winters, producers should select sweet corn hybrids with a high level of resistance or tolerance to Bacterial Wilt (Stewart’s Wilt).
Monitoring: Check corn from emergence until 12 inches tall. Flea beetle stress may be great on late planted corn. However, early planted fields may also show noticeable damage. Treatments may be warranted it there are scattered scratch marks on approximately 50% of plants, especially if field has a history of Stewart's wilt.
Application Alternatives :

Ambush 2 E (permethrin)- Apply as a foliar treatment at 6.4 to 12.8 fl oz per acre to a limit of 76.8 fl oz per acre per season.
Asana XL (esfenvalerate)- Apply as a foliar treatment at 5.8 to 9.6 fl oz per acre to a limit of 96 fl oz per acre per season.
Diazinon 50 W (diazinon)- Apply as a foliar treatment at 1 lb per acre.
Pounce 3.2 EC (permethrin)- Apply as a foliar treatment at 4 to 8 fl oz per acre to a limit of 48 fl oz per acre per season.
Sevin 80 WSP (carbaryl)- Apply as a foliar treatment at 1-1/4 to 2-½ lb per acre to a limit of 8 applications per acre per season. Allow at least 7 days between sprays.
Warrior 1 E (lambda-cyhalothrin)- Apply as a foliar treatment at 2.56 to 3.84 fl oz per are per season to a limit of 3.84 pt per acre per season.