Grape colaspis grub
- Adult: Small brown beetle with yellowish lines running down the length of its wing covers.
- Larvae: Small white grubs with tan or orange heads and covered in tiny hairs.
- Eggs: White to yellow and laid in clusters of about three dozen in the soil.
Timing of damage: VE to V6
Type of damage: Larvae feed on the surface tissue of corn roots, causing wilting and sometimes plant death.
Scouting: Dig up plants and inspect roots and surrounding soil for larvae.
Economic threshold: There is no established threshold as there are no known rescue treatments for grape colaspis damage. Infestations should be noted in future planting decisions.