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Corn flea beetle larvae


  • Adult: Very small shiny black beetles with enlarged hind legs. Easily disturbed and able to jump long distances.
  • Larvae: Small, white with a dark head and fairly inactive.
  • Eggs: White and pointed at one end. 

Timing of damage: VE to V4

Type of damage: Scratches on the upper and lower leaf surfaces usually parallel to the veins. Flea beetles do not chew all the way through the leaves. Primary carrier of Stewart’s bacterial wilt. 

Scouting: Examine 20 plants in five different locations for a total of 100 plants, particularly around the edges of fields. Note the number of beetles per plant and the percentage of plants damaged. 

Economic threshold: Treat when there are five or more beetles per plant and 50% of seedlings have been damaged.

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