Soil applied insectides at planting can be effective at controlling western corn rootworm. Seed treatments can also provide control for low to moderate infestations. Always read and follow all label instructions.
Many Bt traits provide protection against western corn rootworm.
Because western corn rootworms can only complete their lifecycle on corn (and related grasses), crop rotation was once an effective control technique. However, some western corn rootworms adults now bypass this technique by laying eggs on soybeans (so that the larva which hatch the following year are likely to be in a corn field). Nonetheless, fields with high adult pressure one year will likely have high larval pressure the following year and so rotating away from corn in these fields remains a good management strategy.