Japanese beetle grub
- Adult: Metallic green beetle with bronze wing covers about ½" long. There are six tufts of white hair on each side of the abdomen just below the wing covers.
- Larvae: Grubs are creamy white with a brown head capsule, C-shaped and about 1" long.
- Eggs: White to translucent, small and elliptical to spherical in shape.
Timing of damage: V8 to R6
Type of damage: Adults feed on silk and leaves, causing skeletonized defoliation. Grubs feed on
Scouting: Check five plants in each of five locations of a field and note the number of beetles and the extent of silk clipping.
Economic threshold: When silks are cut to less than ½", less than 50% of the field has been
pollinated and beetles are present and feeding.