Mexican bean beetle grub
- Adult: Oval-shaped beetle that is yellow to orange-brown with eight black spots on each wing cover.
- Larvae: Tiny, greenish-yellow, soft-bodied and spiny.
- Eggs: Pale yellow to orange and laid in clusters on the undersides of bean leaves.
Timing of damage: V1 to R7
Type of damage: Both larvae and adults skeletonize bean leaves. Adults will also feed on pods.
Scouting: Examine five plants in five areas of the field to determine percentage of defoliation.
Economic threshold: In V stages: 40% defoliation. R1 to R5: 15% defoliation. R6 to harvest: 25%
defoliation and beetles or larvae are actively feeding.