It is likely that several species of Cyclocephala (annual life cycle) or Phyllophaga (three-year life cycle) can be found in wheat fields in the Great Plains. White grubs are the immature stage of scarab beetles (Cyclocephala—chafer beetles; Phyllophaga—May or June beetles). White grubs are recognized by their white body color, brown head capsule, and C-shaped body.
Larvae of white grubs feed on roots, severing plants at or above the crown. Plants are most vulnerable to this feeding when they are seedlings and have limited root mass. Associated damage may result from vertebrate predators aggressively digging up grubs and destroying plant stands. Damage is most often limited to spotty areas where populations are high or where soil conditions were optimum for egg laying and larval development.