cereal leaf beetle larva 3 MER copy.jpg

Cereal leaf beetle grub


  • Adult: About ¼" long with rust-red legs and a metallic bluish-black head and wing covers.
  • Larvae: Yellowish grubs with dark head and legs; however, coloring is usually obscured by a black glob of mucus and fecal matter on the body that gives a shiny black appearance.
  • Eggs: Elliptical and yellow to brownish yellow. Laid singly or in scattered groups on the upper leaf surface. 

Timing of damage: Spring

Type of damage: Defoliation and skeletonization of leaves. Larvae eat long strips of green tissue from between leaf veins.

Scouting: Scout after majority of eggs have hatched. Take samples from 10 random sites, 
avoiding field edges. At each site, check 10 tillers for eggs and larvae.

Economic threshold: 25 eggs and/or larvae per 100 tillers.

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